diff --git a/po/uk.po b/po/uk.po
index 9471f5e9..e0212fba 100644
--- a/po/uk.po
+++ b/po/uk.po
@@ -52,8 +52,8 @@ msgstr "Локальний запуск Cargo"
 msgid "Day 1: Morning"
 msgstr ""
 
-#: src/SUMMARY.md:19 src/SUMMARY.md:79 src/SUMMARY.md:137 src/SUMMARY.md:195
-#: src/SUMMARY.md:221 src/SUMMARY.md:271
+#: src/SUMMARY.md:19 src/SUMMARY.md:79 src/SUMMARY.md:134 src/SUMMARY.md:192
+#: src/SUMMARY.md:218 src/SUMMARY.md:268
 msgid "Welcome"
 msgstr ""
 
@@ -121,7 +121,7 @@ msgstr ""
 msgid "Rustdoc"
 msgstr ""
 
-#: src/SUMMARY.md:36 src/SUMMARY.md:107 src/basic-syntax/methods.md:1
+#: src/SUMMARY.md:36 src/SUMMARY.md:102 src/basic-syntax/methods.md:1
 #: src/methods.md:1
 msgid "Methods"
 msgstr ""
@@ -130,9 +130,9 @@ msgstr ""
 msgid "Overloading"
 msgstr ""
 
-#: src/SUMMARY.md:38 src/SUMMARY.md:71 src/SUMMARY.md:100 src/SUMMARY.md:110
-#: src/SUMMARY.md:129 src/SUMMARY.md:157 src/SUMMARY.md:187 src/SUMMARY.md:214
-#: src/SUMMARY.md:235 src/SUMMARY.md:263 src/SUMMARY.md:285 src/SUMMARY.md:306
+#: src/SUMMARY.md:38 src/SUMMARY.md:71 src/SUMMARY.md:105 src/SUMMARY.md:125
+#: src/SUMMARY.md:154 src/SUMMARY.md:184 src/SUMMARY.md:211 src/SUMMARY.md:232
+#: src/SUMMARY.md:260 src/SUMMARY.md:282 src/SUMMARY.md:303
 #: src/exercises/android/morning.md:1 src/exercises/bare-metal/morning.md:1
 #: src/exercises/bare-metal/afternoon.md:1
 #: src/exercises/concurrency/morning.md:1
@@ -152,7 +152,7 @@ msgstr ""
 msgid "Day 1: Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:44 src/SUMMARY.md:298 src/control-flow.md:1
+#: src/SUMMARY.md:44 src/SUMMARY.md:295 src/control-flow.md:1
 msgid "Control Flow"
 msgstr ""
 
@@ -285,751 +285,747 @@ msgstr ""
 msgid "Rust Memory Management"
 msgstr ""
 
-#: src/SUMMARY.md:88 src/memory-management/comparison.md:1
-msgid "Comparison"
-msgstr ""
-
-#: src/SUMMARY.md:89 src/ownership.md:1
+#: src/SUMMARY.md:88 src/ownership.md:1
 msgid "Ownership"
 msgstr ""
 
-#: src/SUMMARY.md:90 src/ownership/move-semantics.md:1
+#: src/SUMMARY.md:89 src/ownership/move-semantics.md:1
 msgid "Move Semantics"
 msgstr ""
 
-#: src/SUMMARY.md:91 src/ownership/moved-strings-rust.md:1
+#: src/SUMMARY.md:90 src/ownership/moved-strings-rust.md:1
 msgid "Moved Strings in Rust"
 msgstr ""
 
-#: src/SUMMARY.md:92
+#: src/SUMMARY.md:91
 msgid "Double Frees in Modern C++"
 msgstr ""
 
-#: src/SUMMARY.md:93 src/ownership/moves-function-calls.md:1
+#: src/SUMMARY.md:92 src/ownership/moves-function-calls.md:1
 msgid "Moves in Function Calls"
 msgstr ""
 
-#: src/SUMMARY.md:94 src/ownership/copy-clone.md:1
+#: src/SUMMARY.md:93 src/ownership/copy-clone.md:1
 msgid "Copying and Cloning"
 msgstr ""
 
-#: src/SUMMARY.md:95 src/ownership/borrowing.md:1
+#: src/SUMMARY.md:94 src/ownership/borrowing.md:1
 msgid "Borrowing"
 msgstr ""
 
-#: src/SUMMARY.md:96 src/ownership/shared-unique-borrows.md:1
+#: src/SUMMARY.md:95 src/ownership/shared-unique-borrows.md:1
 msgid "Shared and Unique Borrows"
 msgstr ""
 
-#: src/SUMMARY.md:97 src/ownership/lifetimes.md:1
+#: src/SUMMARY.md:96 src/ownership/lifetimes.md:1
 msgid "Lifetimes"
 msgstr ""
 
-#: src/SUMMARY.md:98 src/ownership/lifetimes-function-calls.md:1
+#: src/SUMMARY.md:97 src/ownership/lifetimes-function-calls.md:1
 msgid "Lifetimes in Function Calls"
 msgstr ""
 
-#: src/SUMMARY.md:99 src/ownership/lifetimes-data-structures.md:1
+#: src/SUMMARY.md:98 src/ownership/lifetimes-data-structures.md:1
 msgid "Lifetimes in Data Structures"
 msgstr ""
 
-#: src/SUMMARY.md:101 src/exercises/day-2/book-library.md:1
-msgid "Storing Books"
-msgstr ""
-
-#: src/SUMMARY.md:102 src/exercises/day-2/iterators-and-ownership.md:1
-msgid "Iterators and Ownership"
-msgstr ""
-
-#: src/SUMMARY.md:104 src/structs.md:1
+#: src/SUMMARY.md:99 src/structs.md:1
 msgid "Structs"
 msgstr ""
 
-#: src/SUMMARY.md:105 src/structs/tuple-structs.md:1
+#: src/SUMMARY.md:100 src/structs/tuple-structs.md:1
 msgid "Tuple Structs"
 msgstr ""
 
-#: src/SUMMARY.md:106 src/structs/field-shorthand.md:1
+#: src/SUMMARY.md:101 src/structs/field-shorthand.md:1
 msgid "Field Shorthand Syntax"
 msgstr ""
 
-#: src/SUMMARY.md:108 src/methods/receiver.md:1
+#: src/SUMMARY.md:103 src/methods/receiver.md:1
 msgid "Method Receiver"
 msgstr ""
 
-#: src/SUMMARY.md:109 src/SUMMARY.md:169 src/SUMMARY.md:284
+#: src/SUMMARY.md:104 src/SUMMARY.md:166 src/SUMMARY.md:281
 #: src/methods/example.md:1 src/concurrency/shared_state/example.md:1
 msgid "Example"
 msgstr ""
 
-#: src/SUMMARY.md:111 src/exercises/day-2/health-statistics.md:1
+#: src/SUMMARY.md:106 src/exercises/day-2/book-library.md:1
+msgid "Storing Books"
+msgstr ""
+
+#: src/SUMMARY.md:107 src/exercises/day-2/health-statistics.md:1
 msgid "Health Statistics"
 msgstr ""
 
-#: src/SUMMARY.md:113
+#: src/SUMMARY.md:109
 msgid "Day 2: Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:115 src/std.md:1
+#: src/SUMMARY.md:111 src/std.md:1
 msgid "Standard Library"
 msgstr ""
 
-#: src/SUMMARY.md:116
+#: src/SUMMARY.md:112
 msgid "Option and Result"
 msgstr ""
 
-#: src/SUMMARY.md:117 src/std/string.md:1
+#: src/SUMMARY.md:113 src/std/string.md:1
 msgid "String"
 msgstr ""
 
-#: src/SUMMARY.md:118
+#: src/SUMMARY.md:114
 msgid "Vec"
 msgstr ""
 
-#: src/SUMMARY.md:119
+#: src/SUMMARY.md:115
 msgid "HashMap"
 msgstr ""
 
-#: src/SUMMARY.md:120
+#: src/SUMMARY.md:116
 msgid "Box"
 msgstr ""
 
-#: src/SUMMARY.md:121
+#: src/SUMMARY.md:117
 msgid "Recursive Data Types"
 msgstr ""
 
-#: src/SUMMARY.md:122 src/std/box-niche.md:1
+#: src/SUMMARY.md:118 src/std/box-niche.md:1
 msgid "Niche Optimization"
 msgstr ""
 
-#: src/SUMMARY.md:123
+#: src/SUMMARY.md:119
 msgid "Rc"
 msgstr ""
 
-#: src/SUMMARY.md:124
+#: src/SUMMARY.md:120
 msgid "Cell/RefCell"
 msgstr ""
 
-#: src/SUMMARY.md:125 src/modules.md:1
+#: src/SUMMARY.md:121 src/modules.md:1
 msgid "Modules"
 msgstr ""
 
-#: src/SUMMARY.md:126 src/modules/visibility.md:1
+#: src/SUMMARY.md:122 src/modules/visibility.md:1
 msgid "Visibility"
 msgstr ""
 
-#: src/SUMMARY.md:127 src/modules/paths.md:1
+#: src/SUMMARY.md:123 src/modules/paths.md:1
 msgid "Paths"
 msgstr ""
 
-#: src/SUMMARY.md:128 src/modules/filesystem.md:1
+#: src/SUMMARY.md:124 src/modules/filesystem.md:1
 msgid "Filesystem Hierarchy"
 msgstr ""
 
-#: src/SUMMARY.md:130 src/exercises/day-2/strings-iterators.md:1
+#: src/SUMMARY.md:126 src/exercises/day-2/iterators-and-ownership.md:1
+msgid "Iterators and Ownership"
+msgstr ""
+
+#: src/SUMMARY.md:127 src/exercises/day-2/strings-iterators.md:1
 #: src/exercises/day-2/solutions-afternoon.md:3
 msgid "Strings and Iterators"
 msgstr ""
 
-#: src/SUMMARY.md:133
+#: src/SUMMARY.md:130
 msgid "Day 3: Morning"
 msgstr ""
 
-#: src/SUMMARY.md:138 src/generics.md:1
+#: src/SUMMARY.md:135 src/generics.md:1
 msgid "Generics"
 msgstr ""
 
-#: src/SUMMARY.md:139 src/generics/data-types.md:1
+#: src/SUMMARY.md:136 src/generics/data-types.md:1
 msgid "Generic Data Types"
 msgstr ""
 
-#: src/SUMMARY.md:140 src/generics/methods.md:1
+#: src/SUMMARY.md:137 src/generics/methods.md:1
 msgid "Generic Methods"
 msgstr ""
 
-#: src/SUMMARY.md:141 src/generics/monomorphization.md:1
+#: src/SUMMARY.md:138 src/generics/monomorphization.md:1
 msgid "Monomorphization"
 msgstr ""
 
-#: src/SUMMARY.md:142 src/traits.md:1
+#: src/SUMMARY.md:139 src/traits.md:1
 msgid "Traits"
 msgstr ""
 
-#: src/SUMMARY.md:143 src/traits/trait-objects.md:1
+#: src/SUMMARY.md:140 src/traits/trait-objects.md:1
 msgid "Trait Objects"
 msgstr ""
 
-#: src/SUMMARY.md:144 src/traits/deriving-traits.md:1
+#: src/SUMMARY.md:141 src/traits/deriving-traits.md:1
 msgid "Deriving Traits"
 msgstr ""
 
-#: src/SUMMARY.md:145 src/traits/default-methods.md:1
+#: src/SUMMARY.md:142 src/traits/default-methods.md:1
 msgid "Default Methods"
 msgstr ""
 
-#: src/SUMMARY.md:146 src/traits/trait-bounds.md:1
+#: src/SUMMARY.md:143 src/traits/trait-bounds.md:1
 msgid "Trait Bounds"
 msgstr ""
 
-#: src/SUMMARY.md:147
+#: src/SUMMARY.md:144
 msgid "impl Trait"
 msgstr ""
 
-#: src/SUMMARY.md:148 src/traits/important-traits.md:1
+#: src/SUMMARY.md:145 src/traits/important-traits.md:1
 msgid "Important Traits"
 msgstr ""
 
-#: src/SUMMARY.md:149
+#: src/SUMMARY.md:146
 msgid "Iterator"
 msgstr ""
 
-#: src/SUMMARY.md:150 src/traits/from-iterator.md:1
+#: src/SUMMARY.md:147 src/traits/from-iterator.md:1
 msgid "FromIterator"
 msgstr ""
 
-#: src/SUMMARY.md:151
+#: src/SUMMARY.md:148
 msgid "From and Into"
 msgstr ""
 
-#: src/SUMMARY.md:152
+#: src/SUMMARY.md:149
 msgid "Read and Write"
 msgstr ""
 
-#: src/SUMMARY.md:153
+#: src/SUMMARY.md:150
 msgid "Drop"
 msgstr ""
 
-#: src/SUMMARY.md:154
+#: src/SUMMARY.md:151
 msgid "Default"
 msgstr ""
 
-#: src/SUMMARY.md:155
+#: src/SUMMARY.md:152
 msgid "Operators: Add, Mul, ..."
 msgstr ""
 
-#: src/SUMMARY.md:156
+#: src/SUMMARY.md:153
 msgid "Closures: Fn, FnMut, FnOnce"
 msgstr ""
 
-#: src/SUMMARY.md:158 src/exercises/day-3/simple-gui.md:1
+#: src/SUMMARY.md:155 src/exercises/day-3/simple-gui.md:1
 #: src/exercises/day-3/solutions-morning.md:3
 msgid "A Simple GUI Library"
 msgstr ""
 
-#: src/SUMMARY.md:159 src/exercises/day-3/solutions-morning.md:175
+#: src/SUMMARY.md:156 src/exercises/day-3/solutions-morning.md:175
 msgid "Points and Polygons"
 msgstr ""
 
-#: src/SUMMARY.md:161
+#: src/SUMMARY.md:158
 msgid "Day 3: Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:163 src/error-handling.md:1
+#: src/SUMMARY.md:160 src/error-handling.md:1
 msgid "Error Handling"
 msgstr ""
 
-#: src/SUMMARY.md:164 src/error-handling/panics.md:1
+#: src/SUMMARY.md:161 src/error-handling/panics.md:1
 msgid "Panics"
 msgstr ""
 
-#: src/SUMMARY.md:165
+#: src/SUMMARY.md:162
 msgid "Catching Stack Unwinding"
 msgstr ""
 
-#: src/SUMMARY.md:166
+#: src/SUMMARY.md:163
 msgid "Structured Error Handling"
 msgstr ""
 
-#: src/SUMMARY.md:167
+#: src/SUMMARY.md:164
 msgid "Propagating Errors with ?"
 msgstr ""
 
-#: src/SUMMARY.md:168 src/error-handling/converting-error-types.md:1
+#: src/SUMMARY.md:165 src/error-handling/converting-error-types.md:1
 #: src/error-handling/converting-error-types-example.md:1
 msgid "Converting Error Types"
 msgstr ""
 
-#: src/SUMMARY.md:170 src/error-handling/deriving-error-enums.md:1
+#: src/SUMMARY.md:167 src/error-handling/deriving-error-enums.md:1
 msgid "Deriving Error Enums"
 msgstr ""
 
-#: src/SUMMARY.md:171 src/error-handling/dynamic-errors.md:1
+#: src/SUMMARY.md:168 src/error-handling/dynamic-errors.md:1
 msgid "Dynamic Error Types"
 msgstr ""
 
-#: src/SUMMARY.md:172 src/error-handling/error-contexts.md:1
+#: src/SUMMARY.md:169 src/error-handling/error-contexts.md:1
 msgid "Adding Context to Errors"
 msgstr ""
 
-#: src/SUMMARY.md:173 src/testing.md:1
+#: src/SUMMARY.md:170 src/testing.md:1
 msgid "Testing"
 msgstr ""
 
-#: src/SUMMARY.md:174 src/testing/unit-tests.md:1
+#: src/SUMMARY.md:171 src/testing/unit-tests.md:1
 msgid "Unit Tests"
 msgstr ""
 
-#: src/SUMMARY.md:175 src/testing/test-modules.md:1
+#: src/SUMMARY.md:172 src/testing/test-modules.md:1
 msgid "Test Modules"
 msgstr ""
 
-#: src/SUMMARY.md:176 src/testing/doc-tests.md:1
+#: src/SUMMARY.md:173 src/testing/doc-tests.md:1
 msgid "Documentation Tests"
 msgstr ""
 
-#: src/SUMMARY.md:177 src/testing/integration-tests.md:1
+#: src/SUMMARY.md:174 src/testing/integration-tests.md:1
 msgid "Integration Tests"
 msgstr ""
 
-#: src/SUMMARY.md:178 src/bare-metal/useful-crates.md:1
+#: src/SUMMARY.md:175 src/bare-metal/useful-crates.md:1
 msgid "Useful crates"
 msgstr ""
 
-#: src/SUMMARY.md:179 src/unsafe.md:1
+#: src/SUMMARY.md:176 src/unsafe.md:1
 msgid "Unsafe Rust"
 msgstr ""
 
-#: src/SUMMARY.md:180 src/unsafe/raw-pointers.md:1
+#: src/SUMMARY.md:177 src/unsafe/raw-pointers.md:1
 msgid "Dereferencing Raw Pointers"
 msgstr ""
 
-#: src/SUMMARY.md:181 src/unsafe/mutable-static-variables.md:1
+#: src/SUMMARY.md:178 src/unsafe/mutable-static-variables.md:1
 msgid "Mutable Static Variables"
 msgstr ""
 
-#: src/SUMMARY.md:182 src/unsafe/unions.md:1
+#: src/SUMMARY.md:179 src/unsafe/unions.md:1
 msgid "Unions"
 msgstr ""
 
-#: src/SUMMARY.md:183 src/unsafe/calling-unsafe-functions.md:1
+#: src/SUMMARY.md:180 src/unsafe/calling-unsafe-functions.md:1
 msgid "Calling Unsafe Functions"
 msgstr ""
 
-#: src/SUMMARY.md:184 src/unsafe/writing-unsafe-functions.md:1
+#: src/SUMMARY.md:181 src/unsafe/writing-unsafe-functions.md:1
 msgid "Writing Unsafe Functions"
 msgstr ""
 
-#: src/SUMMARY.md:185
+#: src/SUMMARY.md:182
 msgid "Extern Functions"
 msgstr ""
 
-#: src/SUMMARY.md:186 src/unsafe/unsafe-traits.md:1
+#: src/SUMMARY.md:183 src/unsafe/unsafe-traits.md:1
 msgid "Implementing Unsafe Traits"
 msgstr ""
 
-#: src/SUMMARY.md:188 src/exercises/day-3/safe-ffi-wrapper.md:1
+#: src/SUMMARY.md:185 src/exercises/day-3/safe-ffi-wrapper.md:1
 #: src/exercises/day-3/solutions-afternoon.md:3
 msgid "Safe FFI Wrapper"
 msgstr ""
 
-#: src/SUMMARY.md:191 src/SUMMARY.md:261 src/bare-metal/android.md:1
+#: src/SUMMARY.md:188 src/SUMMARY.md:258 src/bare-metal/android.md:1
 msgid "Android"
 msgstr ""
 
-#: src/SUMMARY.md:196 src/android/setup.md:1
+#: src/SUMMARY.md:193 src/android/setup.md:1
 msgid "Setup"
 msgstr ""
 
-#: src/SUMMARY.md:197 src/android/build-rules.md:1
+#: src/SUMMARY.md:194 src/android/build-rules.md:1
 msgid "Build Rules"
 msgstr ""
 
-#: src/SUMMARY.md:198
+#: src/SUMMARY.md:195
 msgid "Binary"
 msgstr ""
 
-#: src/SUMMARY.md:199
+#: src/SUMMARY.md:196
 msgid "Library"
 msgstr ""
 
-#: src/SUMMARY.md:200 src/android/aidl.md:1
+#: src/SUMMARY.md:197 src/android/aidl.md:1
 msgid "AIDL"
 msgstr ""
 
-#: src/SUMMARY.md:201
+#: src/SUMMARY.md:198
 msgid "Interface"
 msgstr ""
 
-#: src/SUMMARY.md:202
+#: src/SUMMARY.md:199
 msgid "Implementation"
 msgstr ""
 
-#: src/SUMMARY.md:203
+#: src/SUMMARY.md:200
 msgid "Server"
 msgstr ""
 
-#: src/SUMMARY.md:204 src/android/aidl/deploy.md:1
+#: src/SUMMARY.md:201 src/android/aidl/deploy.md:1
 msgid "Deploy"
 msgstr ""
 
-#: src/SUMMARY.md:205
+#: src/SUMMARY.md:202
 msgid "Client"
 msgstr ""
 
-#: src/SUMMARY.md:206 src/android/aidl/changing.md:1
+#: src/SUMMARY.md:203 src/android/aidl/changing.md:1
 msgid "Changing API"
 msgstr ""
 
-#: src/SUMMARY.md:207 src/SUMMARY.md:251 src/android/logging.md:1
+#: src/SUMMARY.md:204 src/SUMMARY.md:248 src/android/logging.md:1
 #: src/bare-metal/aps/logging.md:1
 msgid "Logging"
 msgstr ""
 
-#: src/SUMMARY.md:208 src/android/interoperability.md:1
+#: src/SUMMARY.md:205 src/android/interoperability.md:1
 msgid "Interoperability"
 msgstr ""
 
-#: src/SUMMARY.md:209
+#: src/SUMMARY.md:206
 msgid "With C"
 msgstr ""
 
-#: src/SUMMARY.md:210
+#: src/SUMMARY.md:207
 msgid "Calling C with Bindgen"
 msgstr ""
 
-#: src/SUMMARY.md:211
+#: src/SUMMARY.md:208
 msgid "Calling Rust from C"
 msgstr ""
 
-#: src/SUMMARY.md:212 src/android/interoperability/cpp.md:1
+#: src/SUMMARY.md:209 src/android/interoperability/cpp.md:1
 msgid "With C++"
 msgstr ""
 
-#: src/SUMMARY.md:213
+#: src/SUMMARY.md:210
 msgid "With Java"
 msgstr ""
 
-#: src/SUMMARY.md:217
+#: src/SUMMARY.md:214
 msgid "Bare Metal: Morning"
 msgstr ""
 
-#: src/SUMMARY.md:222
+#: src/SUMMARY.md:219
 msgid "no_std"
 msgstr ""
 
-#: src/SUMMARY.md:223
+#: src/SUMMARY.md:220
 msgid "A Minimal Example"
 msgstr ""
 
-#: src/SUMMARY.md:224
+#: src/SUMMARY.md:221
 msgid "alloc"
 msgstr ""
 
-#: src/SUMMARY.md:225 src/bare-metal/microcontrollers.md:1
+#: src/SUMMARY.md:222 src/bare-metal/microcontrollers.md:1
 msgid "Microcontrollers"
 msgstr ""
 
-#: src/SUMMARY.md:226 src/bare-metal/microcontrollers/mmio.md:1
+#: src/SUMMARY.md:223 src/bare-metal/microcontrollers/mmio.md:1
 msgid "Raw MMIO"
 msgstr ""
 
-#: src/SUMMARY.md:227
+#: src/SUMMARY.md:224
 msgid "PACs"
 msgstr ""
 
-#: src/SUMMARY.md:228
+#: src/SUMMARY.md:225
 msgid "HAL Crates"
 msgstr ""
 
-#: src/SUMMARY.md:229
+#: src/SUMMARY.md:226
 msgid "Board Support Crates"
 msgstr ""
 
-#: src/SUMMARY.md:230
+#: src/SUMMARY.md:227
 msgid "The Type State Pattern"
 msgstr ""
 
-#: src/SUMMARY.md:231
+#: src/SUMMARY.md:228
 msgid "embedded-hal"
 msgstr ""
 
-#: src/SUMMARY.md:232
+#: src/SUMMARY.md:229
 msgid "probe-rs, cargo-embed"
 msgstr ""
 
-#: src/SUMMARY.md:233 src/bare-metal/microcontrollers/debugging.md:1
+#: src/SUMMARY.md:230 src/bare-metal/microcontrollers/debugging.md:1
 msgid "Debugging"
 msgstr ""
 
-#: src/SUMMARY.md:234 src/SUMMARY.md:254
+#: src/SUMMARY.md:231 src/SUMMARY.md:251
 msgid "Other Projects"
 msgstr ""
 
-#: src/SUMMARY.md:236 src/exercises/bare-metal/compass.md:1
+#: src/SUMMARY.md:233 src/exercises/bare-metal/compass.md:1
 #: src/exercises/bare-metal/solutions-morning.md:3
 msgid "Compass"
 msgstr ""
 
-#: src/SUMMARY.md:238
+#: src/SUMMARY.md:235
 msgid "Bare Metal: Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:240
+#: src/SUMMARY.md:237
 msgid "Application Processors"
 msgstr ""
 
-#: src/SUMMARY.md:241 src/bare-metal/aps/entry-point.md:1
+#: src/SUMMARY.md:238 src/bare-metal/aps/entry-point.md:1
 msgid "Getting Ready to Rust"
 msgstr ""
 
-#: src/SUMMARY.md:242
+#: src/SUMMARY.md:239
 msgid "Inline Assembly"
 msgstr ""
 
-#: src/SUMMARY.md:243
+#: src/SUMMARY.md:240
 msgid "MMIO"
 msgstr ""
 
-#: src/SUMMARY.md:244
+#: src/SUMMARY.md:241
 msgid "Let's Write a UART Driver"
 msgstr ""
 
-#: src/SUMMARY.md:245
+#: src/SUMMARY.md:242
 msgid "More Traits"
 msgstr ""
 
-#: src/SUMMARY.md:246
+#: src/SUMMARY.md:243
 msgid "A Better UART Driver"
 msgstr ""
 
-#: src/SUMMARY.md:247 src/bare-metal/aps/better-uart/bitflags.md:1
+#: src/SUMMARY.md:244 src/bare-metal/aps/better-uart/bitflags.md:1
 msgid "Bitflags"
 msgstr ""
 
-#: src/SUMMARY.md:248
+#: src/SUMMARY.md:245
 msgid "Multiple Registers"
 msgstr ""
 
-#: src/SUMMARY.md:249 src/bare-metal/aps/better-uart/driver.md:1
+#: src/SUMMARY.md:246 src/bare-metal/aps/better-uart/driver.md:1
 msgid "Driver"
 msgstr ""
 
-#: src/SUMMARY.md:250 src/SUMMARY.md:252
+#: src/SUMMARY.md:247 src/SUMMARY.md:249
 msgid "Using It"
 msgstr ""
 
-#: src/SUMMARY.md:253 src/bare-metal/aps/exceptions.md:1
+#: src/SUMMARY.md:250 src/bare-metal/aps/exceptions.md:1
 msgid "Exceptions"
 msgstr ""
 
-#: src/SUMMARY.md:255
+#: src/SUMMARY.md:252
 msgid "Useful Crates"
 msgstr ""
 
-#: src/SUMMARY.md:256
+#: src/SUMMARY.md:253
 msgid "zerocopy"
 msgstr ""
 
-#: src/SUMMARY.md:257
+#: src/SUMMARY.md:254
 msgid "aarch64-paging"
 msgstr ""
 
-#: src/SUMMARY.md:258
+#: src/SUMMARY.md:255
 msgid "buddy_system_allocator"
 msgstr ""
 
-#: src/SUMMARY.md:259
+#: src/SUMMARY.md:256
 msgid "tinyvec"
 msgstr ""
 
-#: src/SUMMARY.md:260
+#: src/SUMMARY.md:257
 msgid "spin"
 msgstr ""
 
-#: src/SUMMARY.md:262 src/bare-metal/android/vmbase.md:1
+#: src/SUMMARY.md:259 src/bare-metal/android/vmbase.md:1
 msgid "vmbase"
 msgstr ""
 
-#: src/SUMMARY.md:264
+#: src/SUMMARY.md:261
 msgid "RTC Driver"
 msgstr ""
 
-#: src/SUMMARY.md:267
+#: src/SUMMARY.md:264
 msgid "Concurrency: Morning"
 msgstr ""
 
-#: src/SUMMARY.md:272 src/concurrency/threads.md:1
+#: src/SUMMARY.md:269 src/concurrency/threads.md:1
 msgid "Threads"
 msgstr ""
 
-#: src/SUMMARY.md:273 src/concurrency/scoped-threads.md:1
+#: src/SUMMARY.md:270 src/concurrency/scoped-threads.md:1
 msgid "Scoped Threads"
 msgstr ""
 
-#: src/SUMMARY.md:274 src/concurrency/channels.md:1
+#: src/SUMMARY.md:271 src/concurrency/channels.md:1
 msgid "Channels"
 msgstr ""
 
-#: src/SUMMARY.md:275 src/concurrency/channels/unbounded.md:1
+#: src/SUMMARY.md:272 src/concurrency/channels/unbounded.md:1
 msgid "Unbounded Channels"
 msgstr ""
 
-#: src/SUMMARY.md:276 src/concurrency/channels/bounded.md:1
+#: src/SUMMARY.md:273 src/concurrency/channels/bounded.md:1
 msgid "Bounded Channels"
 msgstr ""
 
-#: src/SUMMARY.md:277
+#: src/SUMMARY.md:274
 msgid "Send and Sync"
 msgstr ""
 
-#: src/SUMMARY.md:277
+#: src/SUMMARY.md:274
 msgid "Send"
 msgstr ""
 
-#: src/SUMMARY.md:277
+#: src/SUMMARY.md:274
 msgid "Sync"
 msgstr ""
 
-#: src/SUMMARY.md:280 src/concurrency/send-sync/examples.md:1
+#: src/SUMMARY.md:277 src/concurrency/send-sync/examples.md:1
 msgid "Examples"
 msgstr ""
 
-#: src/SUMMARY.md:281 src/concurrency/shared_state.md:1
+#: src/SUMMARY.md:278 src/concurrency/shared_state.md:1
 msgid "Shared State"
 msgstr ""
 
-#: src/SUMMARY.md:282
+#: src/SUMMARY.md:279
 msgid "Arc"
 msgstr ""
 
-#: src/SUMMARY.md:283
+#: src/SUMMARY.md:280
 msgid "Mutex"
 msgstr ""
 
-#: src/SUMMARY.md:286 src/SUMMARY.md:307
+#: src/SUMMARY.md:283 src/SUMMARY.md:304
 #: src/exercises/concurrency/dining-philosophers.md:1
 #: src/exercises/concurrency/solutions-morning.md:3
 msgid "Dining Philosophers"
 msgstr ""
 
-#: src/SUMMARY.md:287 src/exercises/concurrency/link-checker.md:1
+#: src/SUMMARY.md:284 src/exercises/concurrency/link-checker.md:1
 msgid "Multi-threaded Link Checker"
 msgstr ""
 
-#: src/SUMMARY.md:289
+#: src/SUMMARY.md:286
 msgid "Concurrency: Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:291
+#: src/SUMMARY.md:288
 msgid "Async Basics"
 msgstr ""
 
-#: src/SUMMARY.md:292
+#: src/SUMMARY.md:289
 msgid "async/await"
 msgstr ""
 
-#: src/SUMMARY.md:293 src/async/futures.md:1
+#: src/SUMMARY.md:290 src/async/futures.md:1
 msgid "Futures"
 msgstr ""
 
-#: src/SUMMARY.md:294 src/async/runtimes.md:1
+#: src/SUMMARY.md:291 src/async/runtimes.md:1
 msgid "Runtimes"
 msgstr ""
 
-#: src/SUMMARY.md:295 src/async/runtimes/tokio.md:1
+#: src/SUMMARY.md:292 src/async/runtimes/tokio.md:1
 msgid "Tokio"
 msgstr ""
 
-#: src/SUMMARY.md:296 src/exercises/concurrency/link-checker.md:126
-#: src/async/tasks.md:1 src/exercises/concurrency/chat-app.md:140
+#: src/SUMMARY.md:293 src/exercises/concurrency/link-checker.md:126
+#: src/async/tasks.md:1 src/exercises/concurrency/chat-app.md:143
 msgid "Tasks"
 msgstr ""
 
-#: src/SUMMARY.md:297 src/async/channels.md:1
+#: src/SUMMARY.md:294 src/async/channels.md:1
 msgid "Async Channels"
 msgstr ""
 
-#: src/SUMMARY.md:299 src/async/control-flow/join.md:1
+#: src/SUMMARY.md:296 src/async/control-flow/join.md:1
 msgid "Join"
 msgstr ""
 
-#: src/SUMMARY.md:300 src/async/control-flow/select.md:1
+#: src/SUMMARY.md:297 src/async/control-flow/select.md:1
 msgid "Select"
 msgstr ""
 
-#: src/SUMMARY.md:301
+#: src/SUMMARY.md:298
 msgid "Pitfalls"
 msgstr ""
 
-#: src/SUMMARY.md:302
+#: src/SUMMARY.md:299
 msgid "Blocking the Executor"
 msgstr ""
 
-#: src/SUMMARY.md:303 src/async/pitfalls/pin.md:1
+#: src/SUMMARY.md:300 src/async/pitfalls/pin.md:1
 msgid "Pin"
 msgstr ""
 
-#: src/SUMMARY.md:304 src/async/pitfalls/async-traits.md:1
+#: src/SUMMARY.md:301 src/async/pitfalls/async-traits.md:1
 msgid "Async Traits"
 msgstr ""
 
-#: src/SUMMARY.md:305 src/async/pitfalls/cancellation.md:1
+#: src/SUMMARY.md:302 src/async/pitfalls/cancellation.md:1
 #, fuzzy
 msgid "Cancellation"
 msgstr "Встановлення"
 
-#: src/SUMMARY.md:308 src/exercises/concurrency/chat-app.md:1
+#: src/SUMMARY.md:305 src/exercises/concurrency/chat-app.md:1
 #: src/exercises/concurrency/solutions-afternoon.md:119
 msgid "Broadcast Chat Application"
 msgstr ""
 
-#: src/SUMMARY.md:311
+#: src/SUMMARY.md:308
 msgid "Final Words"
 msgstr ""
 
-#: src/SUMMARY.md:315 src/thanks.md:1
+#: src/SUMMARY.md:312 src/thanks.md:1
 msgid "Thanks!"
 msgstr ""
 
-#: src/SUMMARY.md:316
+#: src/SUMMARY.md:313
 msgid "Other Resources"
 msgstr ""
 
-#: src/SUMMARY.md:317 src/credits.md:1
+#: src/SUMMARY.md:314 src/credits.md:1
 msgid "Credits"
 msgstr ""
 
-#: src/SUMMARY.md:320 src/exercises/solutions.md:1
+#: src/SUMMARY.md:317 src/exercises/solutions.md:1
 msgid "Solutions"
 msgstr ""
 
-#: src/SUMMARY.md:325
+#: src/SUMMARY.md:322
 msgid "Day 1 Morning"
 msgstr ""
 
-#: src/SUMMARY.md:326
+#: src/SUMMARY.md:323
 msgid "Day 1 Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:327
+#: src/SUMMARY.md:324
 msgid "Day 2 Morning"
 msgstr ""
 
-#: src/SUMMARY.md:328
+#: src/SUMMARY.md:325
 msgid "Day 2 Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:329
+#: src/SUMMARY.md:326
 msgid "Day 3 Morning"
 msgstr ""
 
-#: src/SUMMARY.md:330
+#: src/SUMMARY.md:327
 msgid "Day 3 Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:331
+#: src/SUMMARY.md:328
 msgid "Bare Metal Rust Morning"
 msgstr ""
 
-#: src/SUMMARY.md:332 src/exercises/bare-metal/solutions-afternoon.md:1
+#: src/SUMMARY.md:329 src/exercises/bare-metal/solutions-afternoon.md:1
 msgid "Bare Metal Rust Afternoon"
 msgstr ""
 
-#: src/SUMMARY.md:333
+#: src/SUMMARY.md:330
 msgid "Concurrency Morning"
 msgstr ""
 
-#: src/SUMMARY.md:334
+#: src/SUMMARY.md:331
 msgid "Concurrency Afternoon"
 msgstr ""
 
@@ -1059,29 +1055,36 @@ msgstr ""
 
 #: src/index.md:11
 msgid ""
+"The latest version of the course can be found at <https://google.github.io/"
+"comprehensive-rust/>. If you are reading somewhere else, please check there "
+"for updates."
+msgstr ""
+
+#: src/index.md:15
+msgid ""
 "The goal of the course is to teach you Rust. We assume you don't know "
 "anything about Rust and hope to:"
 msgstr ""
 "Ціль курсу --- навчити вас мові Rust. Ми припускаємо, що ви нічого не знаєте "
 "про Rust и надіємося:"
 
-#: src/index.md:14
+#: src/index.md:18
 msgid "Give you a comprehensive understanding of the Rust syntax and language."
 msgstr "Дати повне уявлення про синтаксис та семантику Rust."
 
-#: src/index.md:15
+#: src/index.md:19
 msgid "Enable you to modify existing programs and write new programs in Rust."
 msgstr "Навчити працювати з існуючим кодом та писати нові програми на Rust."
 
-#: src/index.md:16
+#: src/index.md:20
 msgid "Show you common Rust idioms."
 msgstr "Показати розповсюджені ідіоми мови Rust."
 
-#: src/index.md:18
+#: src/index.md:22
 msgid "We call the first three course days Rust Fundamentals."
 msgstr ""
 
-#: src/index.md:20
+#: src/index.md:24
 #, fuzzy
 msgid ""
 "Building on this, you're invited to dive into one or more specialized topics:"
@@ -1089,7 +1092,7 @@ msgstr ""
 "Перші три дні познайомлять вас із основами Rust. Після цього вам  "
 "пропонується заглибитися в одну або кілька спеціалізованих тем:"
 
-#: src/index.md:22
+#: src/index.md:26
 msgid ""
 "[Android](android.md): a half-day course on using Rust for Android platform "
 "development (AOSP). This includes interoperability with C, C++, and Java."
@@ -1098,7 +1101,7 @@ msgstr ""
 "для розробки на платформі Android (AOSP). Сюди входить взаємодія з C, C++ та "
 "Java."
 
-#: src/index.md:24
+#: src/index.md:28
 #, fuzzy
 msgid ""
 "[Bare-metal](bare-metal.md): a whole-day class on using Rust for bare-metal "
@@ -1109,7 +1112,7 @@ msgstr ""
 "низькорівневої (embedded) розробки, що охоплює як мікроконтролери, так і "
 "звичайні процесори."
 
-#: src/index.md:27
+#: src/index.md:31
 #, fuzzy
 msgid ""
 "[Concurrency](concurrency.md): a whole-day class on concurrency in Rust. We "
@@ -1122,11 +1125,11 @@ msgstr ""
 "багатозадачність з використанням потоків і м'ютексів), так і async/await "
 "конкурентність (кооперативна багатозадачність з використанням футур)."
 
-#: src/index.md:33
+#: src/index.md:37
 msgid "Non-Goals"
 msgstr "За рамками курсу"
 
-#: src/index.md:35
+#: src/index.md:39
 msgid ""
 "Rust is a large language and we won't be able to cover all of it in a few "
 "days. Some non-goals of this course are:"
@@ -1134,7 +1137,7 @@ msgstr ""
 "Rust --- це об'ємна мова, і ми не зможемо охопити її за кілька днів. Теми, "
 "що виходять за межі курсу:"
 
-#: src/index.md:38
+#: src/index.md:42
 #, fuzzy
 msgid ""
 "Learning how to develop macros: please see [Chapter 19.5 in the Rust Book]"
@@ -1145,11 +1148,11 @@ msgstr ""
 "org/book/ch19-06-macros.html) и [Rust by Example](https://doc.rust-lang.org/"
 "rust-by-example/macros.html)."
 
-#: src/index.md:42
+#: src/index.md:46
 msgid "Assumptions"
 msgstr "Пропозиції"
 
-#: src/index.md:44
+#: src/index.md:48
 #, fuzzy
 msgid ""
 "The course assumes that you already know how to program. Rust is a "
@@ -1161,7 +1164,7 @@ msgstr ""
 "щоб краще пояснити чи підкреслити різницю у підходах до написання коду на "
 "Rust."
 
-#: src/index.md:48
+#: src/index.md:52
 #, fuzzy
 msgid ""
 "If you know how to program in a dynamically-typed language such as Python or "
@@ -1170,7 +1173,7 @@ msgstr ""
 "Якщо ви знаєте, як програмувати мовою з динамічною типізацією, наприклад "
 "Python або JavaScript, ви зможете успішно пройти цей курс."
 
-#: src/index.md:53
+#: src/index.md:57
 msgid ""
 "This is an example of a _speaker note_. We will use these to add additional "
 "information to the slides. This could be key points which the instructor "
@@ -1194,10 +1197,20 @@ msgstr ""
 "Google.."
 
 #: src/running-the-course.md:8
+msgid ""
+"We typically run classes from 10:00 am to 4:00 pm, with a 1 hour lunch break "
+"in the middle. This leaves 2.5 hours for the morning class and 2.5 hours for "
+"the afternoon class. Note that this is just a recommendation: you can also "
+"spend 3 hour on the morning session to give people more time for exercises. "
+"The downside of longer session is that people can become very tired after 6 "
+"full hours of class in the afternoon."
+msgstr ""
+
+#: src/running-the-course.md:16
 msgid "Before you run the course, you will want to:"
 msgstr "Перед проведенням курсу бажано:"
 
-#: src/running-the-course.md:10
+#: src/running-the-course.md:18
 msgid ""
 "Make yourself familiar with the course material. We've included speaker "
 "notes to help highlight the key points (please help us by contributing more "
@@ -1213,7 +1226,7 @@ msgstr ""
 "замітками для викладача, в той час, як основне вікно ви можете демонструвати "
 "класу."
 
-#: src/running-the-course.md:16
+#: src/running-the-course.md:24
 msgid ""
 "Decide on the dates. Since the course takes at least three full days, we "
 "recommend that you schedule the days over two weeks. Course participants "
@@ -1225,7 +1238,7 @@ msgstr ""
 "учасники курсу вважають корисною наявність перерв, оскільки це допомагає їм "
 "краще осмислити інформацію."
 
-#: src/running-the-course.md:21
+#: src/running-the-course.md:29
 msgid ""
 "Find a room large enough for your in-person participants. We recommend a "
 "class size of 15-25 people. That's small enough that people are comfortable "
@@ -1240,7 +1253,7 @@ msgstr ""
 "комфортно ставити запитання, а у викладача залишився час на те, щоб на них "
 "відповідати."
 
-#: src/running-the-course.md:29
+#: src/running-the-course.md:37
 msgid ""
 "On the day of your course, show up to the room a little early to set things "
 "up. We recommend presenting directly using `mdbook serve` running on your "
@@ -1256,7 +1269,7 @@ msgstr ""
 "затримок під час зміни сторінок. Використання ноутбука також дозволить вам "
 "виправляти друкарські помилки в міру їх виявлення вами або учасниками курсу."
 
-#: src/running-the-course.md:35
+#: src/running-the-course.md:43
 msgid ""
 "Let people solve the exercises by themselves or in small groups. We "
 "typically spend 30-45 minutes on exercises in the morning and in the "
@@ -1274,7 +1287,7 @@ msgstr ""
 "рішення, наприклад, показавши, де знайти відповідну інформацію у стандартній "
 "бібліотеці."
 
-#: src/running-the-course.md:43
+#: src/running-the-course.md:51
 msgid ""
 "That is all, good luck running the course! We hope it will be as much fun "
 "for you as it has been for us!"
@@ -1282,7 +1295,7 @@ msgstr ""
 "На цьому все, удачі у проходженні курсу! Ми сподіваємося, що вам буде так "
 "само весело, як і нам!"
 
-#: src/running-the-course.md:46
+#: src/running-the-course.md:54
 msgid ""
 "Please [provide feedback](https://github.com/google/comprehensive-rust/"
 "discussions/86) afterwards so that we can keep improving the course. We "
@@ -1297,14 +1310,20 @@ msgstr ""
 "discussions/100)!"
 
 #: src/running-the-course/course-structure.md:5
-msgid "The course is fast paced and covers a lot of ground:"
-msgstr "Курс проходить у швидкому темпі та охоплює багато питань:"
+msgid "Rust Fundamentals"
+msgstr ""
 
 #: src/running-the-course/course-structure.md:7
+msgid ""
+"The first three days make up [Rust Fundaments](../welcome-day-1.md). The "
+"days are fast paced and we cover a lot of ground:"
+msgstr ""
+
+#: src/running-the-course/course-structure.md:10
 msgid "Day 1: Basic Rust, syntax, control flow, creating and consuming values."
 msgstr ""
 
-#: src/running-the-course/course-structure.md:8
+#: src/running-the-course/course-structure.md:11
 #, fuzzy
 msgid ""
 "Day 2: Memory management, ownership, compound data types, and the standard "
@@ -1312,18 +1331,18 @@ msgid ""
 msgstr ""
 "День 2: Складові типи даних, зіставлення із зразком, стандартна бібліотека."
 
-#: src/running-the-course/course-structure.md:9
+#: src/running-the-course/course-structure.md:12
 #, fuzzy
 msgid "Day 3: Generics, traits, error handling, testing, and unsafe Rust."
 msgstr ""
 "День 3: Трейти та узагальнення, обробка помилок, тестування, небезпечний "
 "Rust."
 
-#: src/running-the-course/course-structure.md:11
+#: src/running-the-course/course-structure.md:14
 msgid "Deep Dives"
 msgstr "Глибоке занурення"
 
-#: src/running-the-course/course-structure.md:13
+#: src/running-the-course/course-structure.md:16
 msgid ""
 "In addition to the 3-day class on Rust Fundamentals, we cover some more "
 "specialized topics:"
@@ -1331,11 +1350,11 @@ msgstr ""
 "На додаток до 3-денного курсу з основ Rust, ми розглянемо ще кілька "
 "спеціалізованих тем:"
 
-#: src/running-the-course/course-structure.md:16
+#: src/running-the-course/course-structure.md:19
 msgid "Rust in Android"
 msgstr ""
 
-#: src/running-the-course/course-structure.md:18
+#: src/running-the-course/course-structure.md:21
 #, fuzzy
 msgid ""
 "The [Rust in Android](../android.md) deep dive is a half-day course on using "
@@ -1346,7 +1365,7 @@ msgstr ""
 "Rust для розробки на Android платформі. Сюди входить взаємодія з C, C++ та "
 "Java."
 
-#: src/running-the-course/course-structure.md:22
+#: src/running-the-course/course-structure.md:25
 msgid ""
 "You will need an [AOSP checkout](https://source.android.com/docs/setup/"
 "download/downloading). Make a checkout of the [course repository](https://"
@@ -1360,7 +1379,7 @@ msgstr ""
 "`src/android/` в кореневий каталог вашого AOSP. Це гарантує, що система "
 "збирання Android побачить файли `Android.bp` в `src/android/`."
 
-#: src/running-the-course/course-structure.md:27
+#: src/running-the-course/course-structure.md:30
 msgid ""
 "Ensure that `adb sync` works with your emulator or real device and pre-build "
 "all Android examples using `src/android/build_all.sh`. Read the script to "
@@ -1371,11 +1390,11 @@ msgstr ""
 "android/build_all.sh`. Прочитайте скрипт, щоб побачити команди, які він "
 "запускає, і переконайтеся, що вони працюють, коли ви запускаєте їх вручну."
 
-#: src/running-the-course/course-structure.md:34
+#: src/running-the-course/course-structure.md:37
 msgid "Bare-Metal Rust"
 msgstr ""
 
-#: src/running-the-course/course-structure.md:36
+#: src/running-the-course/course-structure.md:39
 #, fuzzy
 msgid ""
 "The [Bare-Metal Rust](../bare-metal.md) deep dive is a full day class on "
@@ -1386,7 +1405,7 @@ msgstr ""
 "використання Rust для низькорівневої (embedded) розробки. Розглядаються як "
 "мікроконтролери, так і прикладні процесори."
 
-#: src/running-the-course/course-structure.md:40
+#: src/running-the-course/course-structure.md:43
 msgid ""
 "For the microcontroller part, you will need to buy the [BBC micro:bit]"
 "(https://microbit.org/) v2 development board ahead of time. Everybody will "
@@ -1398,12 +1417,12 @@ msgstr ""
 "встановити кілька пакетів, як описано на [сторінці привітання](../bare-metal."
 "md)."
 
-#: src/running-the-course/course-structure.md:45
+#: src/running-the-course/course-structure.md:48
 #, fuzzy
 msgid "Concurrency in Rust"
 msgstr "Конкурентність"
 
-#: src/running-the-course/course-structure.md:47
+#: src/running-the-course/course-structure.md:50
 #, fuzzy
 msgid ""
 "The [Concurrency in Rust](../concurrency.md) deep dive is a full day class "
@@ -1412,7 +1431,7 @@ msgstr ""
 "[Concurrency Deep Dive](../concurrency.md) це цілий день занять з класичної, "
 "а теж `async`/`await` конкурентності."
 
-#: src/running-the-course/course-structure.md:50
+#: src/running-the-course/course-structure.md:53
 msgid ""
 "You will need a fresh crate set up and the dependencies downloaded and ready "
 "to go. You can then copy/paste the examples into `src/main.rs` to experiment "
@@ -1422,7 +1441,7 @@ msgstr ""
 "готові до роботи. Потім ви можете скопіювати приклади в `src/main.rs`, щоб "
 "поекспериментувати з ними:"
 
-#: src/running-the-course/course-structure.md:54
+#: src/running-the-course/course-structure.md:57
 msgid ""
 "```shell\n"
 "cargo init concurrency\n"
@@ -1432,11 +1451,11 @@ msgid ""
 "```"
 msgstr ""
 
-#: src/running-the-course/course-structure.md:61
+#: src/running-the-course/course-structure.md:64
 msgid "Format"
 msgstr "Формат"
 
-#: src/running-the-course/course-structure.md:63
+#: src/running-the-course/course-structure.md:66
 msgid ""
 "The course is meant to be very interactive and we recommend letting the "
 "questions drive the exploration of Rust!"
@@ -1709,6 +1728,7 @@ msgstr ""
 #: src/why-rust/modern.md:21 src/basic-syntax/compound-types.md:30
 #: src/basic-syntax/references.md:23
 #: src/pattern-matching/destructuring-enums.md:35
+#: src/ownership/double-free-modern-cpp.md:55
 #: src/error-handling/try-operator.md:48
 #: src/error-handling/converting-error-types-example.md:50
 #: src/concurrency/threads.md:30 src/async/async-await.md:25
@@ -3669,8 +3689,8 @@ msgstr ""
 
 #: src/exercises/day-1/for-loops.md:102
 msgid ""
-"An implicit array copy would have occurred.  Since `i32` is a copy type, then "
-"`[i32; 3]` is also a copy type."
+"An implicit array copy would have occurred.  Since `i32` is a copy type, "
+"then `[i32; 3]` is also a copy type."
 msgstr ""
 
 #: src/control-flow.md:3
@@ -5188,8 +5208,8 @@ msgstr ""
 
 #: src/exercises/day-1/luhn.md:12
 msgid ""
-"After doubling a digit, sum the digits. So doubling `7` becomes `14` which "
-"becomes `5`."
+"After doubling a digit, sum the digits if the result is greater than 9. So "
+"doubling `7` becomes `14` which becomes `1 + 4 = 5`."
 msgstr ""
 
 #: src/exercises/day-1/luhn.md:15
@@ -5225,6 +5245,7 @@ msgid ""
 "#[test]\n"
 "fn test_non_digit_cc_number() {\n"
 "    assert!(!luhn(\"foo\"));\n"
+"    assert!(!luhn(\"foo 0 0\"));\n"
 "}\n"
 "\n"
 "#[test]\n"
@@ -5592,27 +5613,20 @@ msgid "Safe and correct like Java, but without a garbage collector."
 msgstr ""
 
 #: src/memory-management/rust.md:6
-msgid ""
-"Depending on which abstraction (or combination of abstractions) you choose, "
-"can be a single unique pointer, reference counted, or atomically reference "
-"counted."
-msgstr ""
-
-#: src/memory-management/rust.md:7
 msgid "Scope-based like C++, but the compiler enforces full adherence."
 msgstr ""
 
-#: src/memory-management/rust.md:8
+#: src/memory-management/rust.md:7
 msgid ""
 "A Rust user can choose the right abstraction for the situation, some even "
 "have no cost at runtime like C."
 msgstr ""
 
-#: src/memory-management/rust.md:10
+#: src/memory-management/rust.md:9
 msgid "Rust achieves this by modeling _ownership_ explicitly."
 msgstr ""
 
-#: src/memory-management/rust.md:14
+#: src/memory-management/rust.md:13
 msgid ""
 "If asked how at this point, you can mention that in Rust this is usually "
 "handled by RAII wrapper types such as [Box](https://doc.rust-lang.org/std/"
@@ -5623,107 +5637,12 @@ msgid ""
 "errors in C."
 msgstr ""
 
-#: src/memory-management/rust.md:16
+#: src/memory-management/rust.md:15
 msgid ""
 "You may be asked about destructors here, the [Drop](https://doc.rust-lang."
 "org/std/ops/trait.Drop.html) trait is the Rust equivalent."
 msgstr ""
 
-#: src/memory-management/comparison.md:3
-msgid "Here is a rough comparison of the memory management techniques."
-msgstr ""
-
-#: src/memory-management/comparison.md:5
-msgid "Pros of Different Memory Management Techniques"
-msgstr ""
-
-#: src/memory-management/comparison.md:7 src/memory-management/comparison.md:22
-msgid "Manual like C:"
-msgstr ""
-
-#: src/memory-management/comparison.md:8 src/memory-management/comparison.md:14
-#: src/memory-management/comparison.md:17
-msgid "No runtime overhead."
-msgstr ""
-
-#: src/memory-management/comparison.md:9 src/memory-management/comparison.md:26
-msgid "Automatic like Java:"
-msgstr ""
-
-#: src/memory-management/comparison.md:10
-msgid "Fully automatic."
-msgstr ""
-
-#: src/memory-management/comparison.md:11
-#: src/memory-management/comparison.md:18
-msgid "Safe and correct."
-msgstr ""
-
-#: src/memory-management/comparison.md:12
-#: src/memory-management/comparison.md:29
-msgid "Scope-based like C++:"
-msgstr ""
-
-#: src/memory-management/comparison.md:13
-msgid "Partially automatic."
-msgstr ""
-
-#: src/memory-management/comparison.md:15
-msgid "Compiler-enforced scope-based like Rust:"
-msgstr ""
-
-#: src/memory-management/comparison.md:16
-msgid "Enforced by compiler."
-msgstr ""
-
-#: src/memory-management/comparison.md:20
-msgid "Cons of Different Memory Management Techniques"
-msgstr ""
-
-#: src/memory-management/comparison.md:23
-msgid "Use-after-free."
-msgstr ""
-
-#: src/memory-management/comparison.md:24
-msgid "Double-frees."
-msgstr ""
-
-#: src/memory-management/comparison.md:25
-msgid "Memory leaks."
-msgstr ""
-
-#: src/memory-management/comparison.md:27
-msgid "Garbage collection pauses."
-msgstr ""
-
-#: src/memory-management/comparison.md:28
-msgid "Destructor delays."
-msgstr ""
-
-#: src/memory-management/comparison.md:30
-msgid "Complex, opt-in by programmer (on C++)."
-msgstr ""
-
-#: src/memory-management/comparison.md:31
-msgid "Circular references can lead to memory leaks"
-msgstr ""
-
-#: src/memory-management/comparison.md:32
-msgid "Potential runtime overhead"
-msgstr ""
-
-#: src/memory-management/comparison.md:33
-msgid "Compiler-enforced and scope-based like Rust:"
-msgstr ""
-
-#: src/memory-management/comparison.md:34
-msgid "Some upfront complexity."
-msgstr ""
-
-#: src/memory-management/comparison.md:35
-msgid "Can reject valid programs."
-msgstr ""
-
 #: src/ownership.md:3
 msgid ""
 "All variable bindings have a _scope_ where they are valid and it is an error "
@@ -5881,7 +5800,7 @@ msgid ""
 msgstr ""
 
 #: src/ownership/double-free-modern-cpp.md:1
-msgid "Extra Work in Modern C++"
+msgid "Defensive Copies in Modern C++"
 msgstr ""
 
 #: src/ownership/double-free-modern-cpp.md:3
@@ -5954,6 +5873,28 @@ msgid ""
 "```"
 msgstr ""
 
+#: src/ownership/double-free-modern-cpp.md:57
+msgid ""
+"C++ has made a slightly different choice than Rust. Because `=` copies data, "
+"the string data has to be cloned. Otherwise we would get a double-free when "
+"either string goes out of scope."
+msgstr ""
+
+#: src/ownership/double-free-modern-cpp.md:61
+msgid ""
+"C++ also has [`std::move`](https://en.cppreference.com/w/cpp/utility/move), "
+"which is used to indicate when a value may be moved from. If the example had "
+"been `s2 = std::move(s1)`, no heap allocation would take place. After the "
+"move, `s1` would be in a valid but unspecified state. Unlike Rust, the "
+"programmer is allowed to keep using `s1`."
+msgstr ""
+
+#: src/ownership/double-free-modern-cpp.md:66
+msgid ""
+"Unlike Rust, `=` in C++ can run arbitrary code as determined by the type "
+"which is being copied or moved."
+msgstr ""
+
 #: src/ownership/moves-function-calls.md:3
 msgid ""
 "When you pass a value to a function, the value is assigned to the function "
@@ -6430,311 +6371,6 @@ msgid ""
 "of the struct itself. Those are very advanced use cases."
 msgstr ""
 
-#: src/exercises/day-2/morning.md:1
-msgid "Day 2: Morning Exercises"
-msgstr ""
-
-#: src/exercises/day-2/morning.md:3
-msgid "We will look at implementing methods in two contexts:"
-msgstr ""
-
-#: src/exercises/day-2/morning.md:5
-msgid "Simple struct which tracks health statistics."
-msgstr ""
-
-#: src/exercises/day-2/morning.md:7
-msgid "Multiple structs and enums for a drawing library."
-msgstr ""
-
-#: src/exercises/day-2/book-library.md:3
-msgid ""
-"We will learn much more about structs and the `Vec<T>` type tomorrow. For "
-"now, you just need to know part of its API:"
-msgstr ""
-
-#: src/exercises/day-2/book-library.md:6
-msgid ""
-"```rust,editable\n"
-"fn main() {\n"
-"    let mut vec = vec![10, 20];\n"
-"    vec.push(30);\n"
-"    let midpoint = vec.len() / 2;\n"
-"    println!(\"middle value: {}\", vec[midpoint]);\n"
-"    for item in &vec {\n"
-"        println!(\"item: {item}\");\n"
-"    }\n"
-"}\n"
-"```"
-msgstr ""
-
-#: src/exercises/day-2/book-library.md:18
-msgid ""
-"Use this to model a library's book collection. Copy the code below to "
-"<https://play.rust-lang.org/> and update the types to make it compile:"
-msgstr ""
-
-#: src/exercises/day-2/book-library.md:21
-msgid ""
-"```rust,should_panic\n"
-"struct Library {\n"
-"    books: Vec<Book>,\n"
-"}\n"
-"\n"
-"struct Book {\n"
-"    title: String,\n"
-"    year: u16,\n"
-"}\n"
-"\n"
-"impl Book {\n"
-"    // This is a constructor, used below.\n"
-"    fn new(title: &str, year: u16) -> Book {\n"
-"        Book {\n"
-"            title: String::from(title),\n"
-"            year,\n"
-"        }\n"
-"    }\n"
-"}\n"
-"\n"
-"// Implement the methods below. Update the `self` parameter to\n"
-"// indicate the method's required level of ownership over the object:\n"
-"//\n"
-"// - `&self` for shared read-only access,\n"
-"// - `&mut self` for unique and mutable access,\n"
-"// - `self` for unique access by value.\n"
-"impl Library {\n"
-"    fn new() -> Library {\n"
-"        todo!(\"Initialize and return a `Library` value\")\n"
-"    }\n"
-"\n"
-"    //fn len(self) -> usize {\n"
-"    //    todo!(\"Return the length of `self.books`\")\n"
-"    //}\n"
-"\n"
-"    //fn is_empty(self) -> bool {\n"
-"    //    todo!(\"Return `true` if `self.books` is empty\")\n"
-"    //}\n"
-"\n"
-"    //fn add_book(self, book: Book) {\n"
-"    //    todo!(\"Add a new book to `self.books`\")\n"
-"    //}\n"
-"\n"
-"    //fn print_books(self) {\n"
-"    //    todo!(\"Iterate over `self.books` and each book's title and "
-"year\")\n"
-"    //}\n"
-"\n"
-"    //fn oldest_book(self) -> Option<&Book> {\n"
-"    //    todo!(\"Return a reference to the oldest book (if any)\")\n"
-"    //}\n"
-"}\n"
-"\n"
-"// This shows the desired behavior. Uncomment the code below and\n"
-"// implement the missing methods. You will need to update the\n"
-"// method signatures, including the \"self\" parameter! You may\n"
-"// also need to update the variable bindings within main.\n"
-"fn main() {\n"
-"    let library = Library::new();\n"
-"\n"
-"    //println!(\"The library is empty: library.is_empty() -> {}\", library."
-"is_empty());\n"
-"    //\n"
-"    //library.add_book(Book::new(\"Lord of the Rings\", 1954));\n"
-"    //library.add_book(Book::new(\"Alice's Adventures in Wonderland\", "
-"1865));\n"
-"    //\n"
-"    //println!(\"The library is no longer empty: library.is_empty() -> {}\", "
-"library.is_empty());\n"
-"    //\n"
-"    //\n"
-"    //library.print_books();\n"
-"    //\n"
-"    //match library.oldest_book() {\n"
-"    //    Some(book) => println!(\"The oldest book is {}\", book.title),\n"
-"    //    None => println!(\"The library is empty!\"),\n"
-"    //}\n"
-"    //\n"
-"    //println!(\"The library has {} books\", library.len());\n"
-"    //library.print_books();\n"
-"}\n"
-"```"
-msgstr ""
-
-#: src/exercises/day-2/book-library.md:102
-msgid "[Solution](solutions-afternoon.md#designing-a-library)"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:3
-msgid ""
-"The ownership model of Rust affects many APIs. An example of this is the "
-"[`Iterator`](https://doc.rust-lang.org/std/iter/trait.Iterator.html) and "
-"[`IntoIterator`](https://doc.rust-lang.org/std/iter/trait.IntoIterator.html) "
-"traits."
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:8 src/bare-metal/no_std.md:28
-msgid "`Iterator`"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:10
-msgid ""
-"Traits are like interfaces: they describe behavior (methods) for a type. The "
-"`Iterator` trait simply says that you can call `next` until you get `None` "
-"back:"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:13
-msgid ""
-"```rust\n"
-"pub trait Iterator {\n"
-"    type Item;\n"
-"    fn next(&mut self) -> Option<Self::Item>;\n"
-"}\n"
-"```"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:20
-msgid "You use this trait like this:"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:22
-msgid ""
-"```rust,editable\n"
-"fn main() {\n"
-"    let v: Vec<i8> = vec![10, 20, 30];\n"
-"    let mut iter = v.iter();\n"
-"\n"
-"    println!(\"v[0]: {:?}\", iter.next());\n"
-"    println!(\"v[1]: {:?}\", iter.next());\n"
-"    println!(\"v[2]: {:?}\", iter.next());\n"
-"    println!(\"No more items: {:?}\", iter.next());\n"
-"}\n"
-"```"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:34
-msgid "What is the type returned by the iterator? Test your answer here:"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:36
-msgid ""
-"```rust,editable,compile_fail\n"
-"fn main() {\n"
-"    let v: Vec<i8> = vec![10, 20, 30];\n"
-"    let mut iter = v.iter();\n"
-"\n"
-"    let v0: Option<..> = iter.next();\n"
-"    println!(\"v0: {v0:?}\");\n"
-"}\n"
-"```"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:46
-msgid "Why is this type used?"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:48
-msgid "`IntoIterator`"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:50
-msgid ""
-"The `Iterator` trait tells you how to _iterate_ once you have created an "
-"iterator. The related trait `IntoIterator` tells you how to create the "
-"iterator:"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:53
-msgid ""
-"```rust\n"
-"pub trait IntoIterator {\n"
-"    type Item;\n"
-"    type IntoIter: Iterator<Item = Self::Item>;\n"
-"\n"
-"    fn into_iter(self) -> Self::IntoIter;\n"
-"}\n"
-"```"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:62
-msgid ""
-"The syntax here means that every implementation of `IntoIterator` must "
-"declare two types:"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:65
-msgid "`Item`: the type we iterate over, such as `i8`,"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:66
-msgid "`IntoIter`: the `Iterator` type returned by the `into_iter` method."
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:68
-msgid ""
-"Note that `IntoIter` and `Item` are linked: the iterator must have the same "
-"`Item` type, which means that it returns `Option<Item>`"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:71
-msgid "Like before, what  is the type returned by the iterator?"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:73
-msgid ""
-"```rust,editable,compile_fail\n"
-"fn main() {\n"
-"    let v: Vec<String> = vec![String::from(\"foo\"), String::"
-"from(\"bar\")];\n"
-"    let mut iter = v.into_iter();\n"
-"\n"
-"    let v0: Option<..> = iter.next();\n"
-"    println!(\"v0: {v0:?}\");\n"
-"}\n"
-"```"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:83
-msgid "`for` Loops"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:85
-msgid ""
-"Now that we know both `Iterator` and `IntoIterator`, we can build `for` "
-"loops. They call `into_iter()` on an expression and iterates over the "
-"resulting iterator:"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:89
-msgid ""
-"```rust,editable\n"
-"fn main() {\n"
-"    let v: Vec<String> = vec![String::from(\"foo\"), String::"
-"from(\"bar\")];\n"
-"\n"
-"    for word in &v {\n"
-"        println!(\"word: {word}\");\n"
-"    }\n"
-"\n"
-"    for word in v {\n"
-"        println!(\"word: {word}\");\n"
-"    }\n"
-"}\n"
-"```"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:103
-msgid "What is the type of `word` in each loop?"
-msgstr ""
-
-#: src/exercises/day-2/iterators-and-ownership.md:105
-msgid ""
-"Experiment with the code above and then consult the documentation for [`impl "
-"IntoIterator for &Vec<T>`](https://doc.rust-lang.org/std/vec/struct.Vec."
-"html#impl-IntoIterator-for-%26'a+Vec%3CT,+A%3E) and [`impl IntoIterator for "
-"Vec<T>`](https://doc.rust-lang.org/std/vec/struct.Vec.html#impl-IntoIterator-"
-"for-Vec%3CT,+A%3E) to check your answers."
-msgstr ""
-
 #: src/structs.md:3
 msgid "Like C and C++, Rust has support for custom structs:"
 msgstr ""
@@ -7195,12 +6831,137 @@ msgid ""
 "over. We describe vectors in more detail in the afternoon. "
 msgstr ""
 
-#: src/exercises/day-2/afternoon.md:1
-msgid "Day 2: Afternoon Exercises"
+#: src/exercises/day-2/morning.md:1
+msgid "Day 2: Morning Exercises"
 msgstr ""
 
-#: src/exercises/day-2/afternoon.md:3
-msgid "The exercises for this afternoon will focus on strings and iterators."
+#: src/exercises/day-2/morning.md:3
+msgid "We will look at implementing methods in two contexts:"
+msgstr ""
+
+#: src/exercises/day-2/morning.md:5
+msgid "Storing books and querying the collection"
+msgstr ""
+
+#: src/exercises/day-2/morning.md:7
+msgid "Keeping track of health statistics for patients"
+msgstr ""
+
+#: src/exercises/day-2/book-library.md:3
+msgid ""
+"We will learn much more about structs and the `Vec<T>` type tomorrow. For "
+"now, you just need to know part of its API:"
+msgstr ""
+
+#: src/exercises/day-2/book-library.md:6
+msgid ""
+"```rust,editable\n"
+"fn main() {\n"
+"    let mut vec = vec![10, 20];\n"
+"    vec.push(30);\n"
+"    let midpoint = vec.len() / 2;\n"
+"    println!(\"middle value: {}\", vec[midpoint]);\n"
+"    for item in &vec {\n"
+"        println!(\"item: {item}\");\n"
+"    }\n"
+"}\n"
+"```"
+msgstr ""
+
+#: src/exercises/day-2/book-library.md:18
+msgid ""
+"Use this to model a library's book collection. Copy the code below to "
+"<https://play.rust-lang.org/> and update the types to make it compile:"
+msgstr ""
+
+#: src/exercises/day-2/book-library.md:21
+msgid ""
+"```rust,should_panic\n"
+"struct Library {\n"
+"    books: Vec<Book>,\n"
+"}\n"
+"\n"
+"struct Book {\n"
+"    title: String,\n"
+"    year: u16,\n"
+"}\n"
+"\n"
+"impl Book {\n"
+"    // This is a constructor, used below.\n"
+"    fn new(title: &str, year: u16) -> Book {\n"
+"        Book {\n"
+"            title: String::from(title),\n"
+"            year,\n"
+"        }\n"
+"    }\n"
+"}\n"
+"\n"
+"// Implement the methods below. Update the `self` parameter to\n"
+"// indicate the method's required level of ownership over the object:\n"
+"//\n"
+"// - `&self` for shared read-only access,\n"
+"// - `&mut self` for unique and mutable access,\n"
+"// - `self` for unique access by value.\n"
+"impl Library {\n"
+"    fn new() -> Library {\n"
+"        todo!(\"Initialize and return a `Library` value\")\n"
+"    }\n"
+"\n"
+"    //fn len(self) -> usize {\n"
+"    //    todo!(\"Return the length of `self.books`\")\n"
+"    //}\n"
+"\n"
+"    //fn is_empty(self) -> bool {\n"
+"    //    todo!(\"Return `true` if `self.books` is empty\")\n"
+"    //}\n"
+"\n"
+"    //fn add_book(self, book: Book) {\n"
+"    //    todo!(\"Add a new book to `self.books`\")\n"
+"    //}\n"
+"\n"
+"    //fn print_books(self) {\n"
+"    //    todo!(\"Iterate over `self.books` and print each book's title and "
+"year\")\n"
+"    //}\n"
+"\n"
+"    //fn oldest_book(self) -> Option<&Book> {\n"
+"    //    todo!(\"Return a reference to the oldest book (if any)\")\n"
+"    //}\n"
+"}\n"
+"\n"
+"// This shows the desired behavior. Uncomment the code below and\n"
+"// implement the missing methods. You will need to update the\n"
+"// method signatures, including the \"self\" parameter! You may\n"
+"// also need to update the variable bindings within main.\n"
+"fn main() {\n"
+"    let library = Library::new();\n"
+"\n"
+"    //println!(\"The library is empty: library.is_empty() -> {}\", library."
+"is_empty());\n"
+"    //\n"
+"    //library.add_book(Book::new(\"Lord of the Rings\", 1954));\n"
+"    //library.add_book(Book::new(\"Alice's Adventures in Wonderland\", "
+"1865));\n"
+"    //\n"
+"    //println!(\"The library is no longer empty: library.is_empty() -> {}\", "
+"library.is_empty());\n"
+"    //\n"
+"    //\n"
+"    //library.print_books();\n"
+"    //\n"
+"    //match library.oldest_book() {\n"
+"    //    Some(book) => println!(\"The oldest book is {}\", book.title),\n"
+"    //    None => println!(\"The library is empty!\"),\n"
+"    //}\n"
+"    //\n"
+"    //println!(\"The library has {} books\", library.len());\n"
+"    //library.print_books();\n"
+"}\n"
+"```"
+msgstr ""
+
+#: src/exercises/day-2/book-library.md:102
+msgid "[Solution](solutions-afternoon.md#designing-a-library)"
 msgstr ""
 
 #: src/exercises/day-2/health-statistics.md:3
@@ -8327,6 +8088,186 @@ msgid ""
 "in a file named `some_module_test.rs`, similar to the convention in Go."
 msgstr ""
 
+#: src/exercises/day-2/afternoon.md:1
+msgid "Day 2: Afternoon Exercises"
+msgstr ""
+
+#: src/exercises/day-2/afternoon.md:3
+msgid "The exercises for this afternoon will focus on strings and iterators."
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:3
+msgid ""
+"The ownership model of Rust affects many APIs. An example of this is the "
+"[`Iterator`](https://doc.rust-lang.org/std/iter/trait.Iterator.html) and "
+"[`IntoIterator`](https://doc.rust-lang.org/std/iter/trait.IntoIterator.html) "
+"traits."
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:8 src/bare-metal/no_std.md:28
+msgid "`Iterator`"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:10
+msgid ""
+"Traits are like interfaces: they describe behavior (methods) for a type. The "
+"`Iterator` trait simply says that you can call `next` until you get `None` "
+"back:"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:13
+msgid ""
+"```rust\n"
+"pub trait Iterator {\n"
+"    type Item;\n"
+"    fn next(&mut self) -> Option<Self::Item>;\n"
+"}\n"
+"```"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:20
+msgid "You use this trait like this:"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:22
+msgid ""
+"```rust,editable\n"
+"fn main() {\n"
+"    let v: Vec<i8> = vec![10, 20, 30];\n"
+"    let mut iter = v.iter();\n"
+"\n"
+"    println!(\"v[0]: {:?}\", iter.next());\n"
+"    println!(\"v[1]: {:?}\", iter.next());\n"
+"    println!(\"v[2]: {:?}\", iter.next());\n"
+"    println!(\"No more items: {:?}\", iter.next());\n"
+"}\n"
+"```"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:34
+msgid "What is the type returned by the iterator? Test your answer here:"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:36
+msgid ""
+"```rust,editable,compile_fail\n"
+"fn main() {\n"
+"    let v: Vec<i8> = vec![10, 20, 30];\n"
+"    let mut iter = v.iter();\n"
+"\n"
+"    let v0: Option<..> = iter.next();\n"
+"    println!(\"v0: {v0:?}\");\n"
+"}\n"
+"```"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:46
+msgid "Why is this type used?"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:48
+msgid "`IntoIterator`"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:50
+msgid ""
+"The `Iterator` trait tells you how to _iterate_ once you have created an "
+"iterator. The related trait `IntoIterator` tells you how to create the "
+"iterator:"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:53
+msgid ""
+"```rust\n"
+"pub trait IntoIterator {\n"
+"    type Item;\n"
+"    type IntoIter: Iterator<Item = Self::Item>;\n"
+"\n"
+"    fn into_iter(self) -> Self::IntoIter;\n"
+"}\n"
+"```"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:62
+msgid ""
+"The syntax here means that every implementation of `IntoIterator` must "
+"declare two types:"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:65
+msgid "`Item`: the type we iterate over, such as `i8`,"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:66
+msgid "`IntoIter`: the `Iterator` type returned by the `into_iter` method."
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:68
+msgid ""
+"Note that `IntoIter` and `Item` are linked: the iterator must have the same "
+"`Item` type, which means that it returns `Option<Item>`"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:71
+msgid "Like before, what  is the type returned by the iterator?"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:73
+msgid ""
+"```rust,editable,compile_fail\n"
+"fn main() {\n"
+"    let v: Vec<String> = vec![String::from(\"foo\"), String::"
+"from(\"bar\")];\n"
+"    let mut iter = v.into_iter();\n"
+"\n"
+"    let v0: Option<..> = iter.next();\n"
+"    println!(\"v0: {v0:?}\");\n"
+"}\n"
+"```"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:83
+msgid "`for` Loops"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:85
+msgid ""
+"Now that we know both `Iterator` and `IntoIterator`, we can build `for` "
+"loops. They call `into_iter()` on an expression and iterates over the "
+"resulting iterator:"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:89
+msgid ""
+"```rust,editable\n"
+"fn main() {\n"
+"    let v: Vec<String> = vec![String::from(\"foo\"), String::"
+"from(\"bar\")];\n"
+"\n"
+"    for word in &v {\n"
+"        println!(\"word: {word}\");\n"
+"    }\n"
+"\n"
+"    for word in v {\n"
+"        println!(\"word: {word}\");\n"
+"    }\n"
+"}\n"
+"```"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:103
+msgid "What is the type of `word` in each loop?"
+msgstr ""
+
+#: src/exercises/day-2/iterators-and-ownership.md:105
+msgid ""
+"Experiment with the code above and then consult the documentation for [`impl "
+"IntoIterator for &Vec<T>`](https://doc.rust-lang.org/std/vec/struct.Vec."
+"html#impl-IntoIterator-for-%26'a+Vec%3CT,+A%3E) and [`impl IntoIterator for "
+"Vec<T>`](https://doc.rust-lang.org/std/vec/struct.Vec.html#impl-IntoIterator-"
+"for-Vec%3CT,+A%3E) to check your answers."
+msgstr ""
+
 #: src/exercises/day-2/strings-iterators.md:3
 msgid ""
 "In this exercise, you are implementing a routing component of a web server. "
@@ -17813,7 +17754,7 @@ msgid ""
 "In this example, we have a race between a cat and a dog. "
 "`first_animal_to_finish_race` listens to both channels and will pick "
 "whichever arrives first. Since the dog takes 50ms, it wins against the cat "
-"that take 500ms seconds."
+"that take 500ms."
 msgstr ""
 
 #: src/async/control-flow/select.md:67
@@ -18272,7 +18213,7 @@ msgstr ""
 
 #: src/async/pitfalls/cancellation.md:82
 msgid ""
-"`LinesReader` can be made cancellation-safe by makeing `buf` part of the "
+"`LinesReader` can be made cancellation-safe by making `buf` part of the "
 "struct:"
 msgstr ""
 
@@ -18447,7 +18388,7 @@ msgstr ""
 msgid ""
 "For this, we use [a broadcast channel](https://docs.rs/tokio/latest/tokio/"
 "sync/broadcast/fn.channel.html) on the server, and [`tokio_websockets`]"
-"(https://docs.rs/tokio-websockets/0.3.2/tokio_websockets/) for the "
+"(https://docs.rs/tokio-websockets/0.4.0/tokio_websockets/) for the "
 "communication between the client and the server."
 msgstr ""
 
@@ -18468,10 +18409,11 @@ msgid ""
 "edition = \"2021\"\n"
 "\n"
 "[dependencies]\n"
-"futures-util = \"0.3.28\"\n"
+"futures-util = { version = \"0.3.28\", features = [\"sink\"] }\n"
 "http = \"0.2.9\"\n"
 "tokio = { version = \"1.28.1\", features = [\"full\"] }\n"
-"tokio-websockets = \"0.3.2\"\n"
+"tokio-websockets = { version = \"0.4.0\", features = [\"client\", "
+"\"fastrand\", \"server\", \"sha1_smol\"] }\n"
 "```"
 msgstr ""
 
@@ -18482,15 +18424,15 @@ msgstr ""
 #: src/exercises/concurrency/chat-app.md:33
 msgid ""
 "You are going to need the following functions from `tokio` and "
-"[`tokio_websockets`](https://docs.rs/tokio-websockets/0.3.2/"
+"[`tokio_websockets`](https://docs.rs/tokio-websockets/0.4.0/"
 "tokio_websockets/). Spend a few minutes to familiarize yourself with the "
 "API. "
 msgstr ""
 
 #: src/exercises/concurrency/chat-app.md:37
 msgid ""
-"[WebsocketStream::next()](https://docs.rs/tokio-websockets/0.3.2/"
-"tokio_websockets/proto/struct.WebsocketStream.html#method.next): for "
+"[StreamExt::next()](https://docs.rs/futures-util/0.3.28/futures_util/stream/"
+"trait.StreamExt.html#method.next) implemented by `WebsocketStream`: for "
 "asynchronously reading messages from a Websocket Stream."
 msgstr ""
 
@@ -18545,6 +18487,7 @@ msgstr ""
 msgid ""
 "```rust,compile_fail\n"
 "use futures_util::sink::SinkExt;\n"
+"use futures_util::stream::StreamExt;\n"
 "use std::error::Error;\n"
 "use std::net::SocketAddr;\n"
 "use tokio::net::{TcpListener, TcpStream};\n"
@@ -18583,14 +18526,15 @@ msgid ""
 "```"
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:102
-#: src/exercises/concurrency/solutions-afternoon.md:208
+#: src/exercises/concurrency/chat-app.md:103
+#: src/exercises/concurrency/solutions-afternoon.md:210
 msgid "`src/bin/client.rs`:"
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:106
+#: src/exercises/concurrency/chat-app.md:107
 msgid ""
 "```rust,compile_fail\n"
+"use futures_util::stream::StreamExt;\n"
 "use futures_util::SinkExt;\n"
 "use http::Uri;\n"
 "use tokio::io::{AsyncBufReadExt, BufReader};\n"
@@ -18598,10 +18542,10 @@ msgid ""
 "\n"
 "#[tokio::main]\n"
 "async fn main() -> Result<(), tokio_websockets::Error> {\n"
-"    let mut ws_stream = ClientBuilder::from_uri(Uri::"
-"from_static(\"ws://127.0.0.1:2000\"))\n"
-"        .connect()\n"
-"        .await?;\n"
+"    let (mut ws_stream, _) =\n"
+"        ClientBuilder::from_uri(Uri::from_static(\"ws://127.0.0.1:2000\"))\n"
+"            .connect()\n"
+"            .await?;\n"
 "\n"
 "    let stdin = tokio::io::stdin();\n"
 "    let mut stdin = BufReader::new(stdin).lines();\n"
@@ -18613,48 +18557,48 @@ msgid ""
 "```"
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:127
+#: src/exercises/concurrency/chat-app.md:130
 msgid "Running the binaries"
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:128
+#: src/exercises/concurrency/chat-app.md:131
 msgid "Run the server with:"
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:130
+#: src/exercises/concurrency/chat-app.md:133
 msgid ""
 "```shell\n"
 "cargo run --bin server\n"
 "```"
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:134
+#: src/exercises/concurrency/chat-app.md:137
 msgid "and the client with:"
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:136
+#: src/exercises/concurrency/chat-app.md:139
 msgid ""
 "```shell\n"
 "cargo run --bin client\n"
 "```"
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:142
+#: src/exercises/concurrency/chat-app.md:145
 msgid "Implement the `handle_connection` function in `src/bin/server.rs`."
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:143
+#: src/exercises/concurrency/chat-app.md:146
 msgid ""
 "Hint: Use `tokio::select!` for concurrently performing two tasks in a "
 "continuous loop. One task receives messages from the client and broadcasts "
 "them. The other sends messages received by the server to the client."
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:146
+#: src/exercises/concurrency/chat-app.md:149
 msgid "Complete the main function in `src/bin/client.rs`."
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:147
+#: src/exercises/concurrency/chat-app.md:150
 msgid ""
 "Hint: As before, use `tokio::select!` in a continuous loop for concurrently "
 "performing two tasks: (1) reading user messages from standard input and "
@@ -18662,7 +18606,7 @@ msgid ""
 "displaying them for the user."
 msgstr ""
 
-#: src/exercises/concurrency/chat-app.md:151
+#: src/exercises/concurrency/chat-app.md:154
 msgid ""
 "Optional: Once you are done, change the code to broadcast messages to all "
 "clients, but the sender of the message."
@@ -19092,6 +19036,7 @@ msgid ""
 "#[test]\n"
 "fn test_non_digit_cc_number() {\n"
 "    assert!(!luhn(\"foo\"));\n"
+"    assert!(!luhn(\"foo 0 0\"));\n"
 "}\n"
 "\n"
 "#[test]\n"
@@ -19129,11 +19074,11 @@ msgid ""
 "```"
 msgstr ""
 
-#: src/exercises/day-1/solutions-afternoon.md:97
+#: src/exercises/day-1/solutions-afternoon.md:98
 msgid "Pattern matching"
 msgstr ""
 
-#: src/exercises/day-1/solutions-afternoon.md:99
+#: src/exercises/day-1/solutions-afternoon.md:100
 msgid "TBD."
 msgstr ""
 
@@ -19230,7 +19175,7 @@ msgid ""
 "\n"
 "    // ANCHOR: Library_print_books\n"
 "    //fn print_books(self) {\n"
-"    //    todo!(\"Iterate over `self.books` and each book's title and "
+"    //    todo!(\"Iterate over `self.books` and print each book's title and "
 "year\")\n"
 "    //}\n"
 "    // ANCHOR_END: Library_print_books\n"
@@ -20999,6 +20944,7 @@ msgid ""
 "\n"
 "// ANCHOR: setup\n"
 "use futures_util::sink::SinkExt;\n"
+"use futures_util::stream::StreamExt;\n"
 "use std::error::Error;\n"
 "use std::net::SocketAddr;\n"
 "use tokio::net::{TcpListener, TcpStream};\n"
@@ -21028,9 +20974,10 @@ msgid ""
 "            incoming = ws_stream.next() => {\n"
 "                match incoming {\n"
 "                    Some(Ok(msg)) => {\n"
-"                        let msg = msg.as_text()?;\n"
-"                        println!(\"From client {addr:?} {msg:?}\");\n"
-"                        bcast_tx.send(msg.into())?;\n"
+"                        if let Some(text) = msg.as_text() {\n"
+"                            println!(\"From client {addr:?} {text:?}\");\n"
+"                            bcast_tx.send(text.into())?;\n"
+"                        }\n"
 "                    }\n"
 "                    Some(Err(err)) => return Err(err.into()),\n"
 "                    None => return Ok(()),\n"
@@ -21067,7 +21014,7 @@ msgid ""
 "```"
 msgstr ""
 
-#: src/exercises/concurrency/solutions-afternoon.md:210
+#: src/exercises/concurrency/solutions-afternoon.md:212
 msgid ""
 "```rust,compile_fail\n"
 "// Copyright 2023 Google LLC\n"
@@ -21085,6 +21032,7 @@ msgid ""
 "// limitations under the License.\n"
 "\n"
 "// ANCHOR: setup\n"
+"use futures_util::stream::StreamExt;\n"
 "use futures_util::SinkExt;\n"
 "use http::Uri;\n"
 "use tokio::io::{AsyncBufReadExt, BufReader};\n"
@@ -21092,10 +21040,10 @@ msgid ""
 "\n"
 "#[tokio::main]\n"
 "async fn main() -> Result<(), tokio_websockets::Error> {\n"
-"    let mut ws_stream = ClientBuilder::from_uri(Uri::"
-"from_static(\"ws://127.0.0.1:2000\"))\n"
-"        .connect()\n"
-"        .await?;\n"
+"    let (mut ws_stream, _) =\n"
+"        ClientBuilder::from_uri(Uri::from_static(\"ws://127.0.0.1:2000\"))\n"
+"            .connect()\n"
+"            .await?;\n"
 "\n"
 "    let stdin = tokio::io::stdin();\n"
 "    let mut stdin = BufReader::new(stdin).lines();\n"
@@ -21106,8 +21054,11 @@ msgid ""
 "        tokio::select! {\n"
 "            incoming = ws_stream.next() => {\n"
 "                match incoming {\n"
-"                    Some(Ok(msg)) => println!(\"From server: {}\", msg."
-"as_text()?),\n"
+"                    Some(Ok(msg)) => {\n"
+"                        if let Some(text) = msg.as_text() {\n"
+"                            println!(\"From server: {}\", text);\n"
+"                        }\n"
+"                    },\n"
 "                    Some(Err(err)) => return Err(err.into()),\n"
 "                    None => return Ok(()),\n"
 "                }\n"
@@ -21127,6 +21078,9 @@ msgid ""
 "```"
 msgstr ""
 
+#~ msgid "The course is fast paced and covers a lot of ground:"
+#~ msgstr "Курс проходить у швидкому темпі та охоплює багато питань:"
+
 #~ msgid "Day 1: Basic Rust, ownership and the borrow checker."
 #~ msgstr "День 1: Базовий Rust, володіння та аналізатор запозичень"