2018-02-22 08:09:53 +02:00
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// iterators4.rs
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2022-07-14 18:29:09 +02:00
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// Execute `rustlings hint iterators4` or use the `hint` watch subcommand for a hint.
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2018-02-22 08:09:53 +02:00
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2019-11-11 14:38:24 +02:00
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// I AM NOT DONE
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2017-01-06 05:38:07 +02:00
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pub fn factorial(num: u64) -> u64 {
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2020-04-30 04:11:54 +02:00
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// Complete this function to return the factorial of num
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2017-01-06 05:38:07 +02:00
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// Do not use:
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// - return
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2020-04-30 04:11:54 +02:00
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// Try not to use:
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2017-01-06 05:38:07 +02:00
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// - imperative style loops (for, while)
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// - additional variables
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2020-04-30 04:11:54 +02:00
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// For an extra challenge, don't use:
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2017-01-06 05:38:07 +02:00
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// - recursion
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2019-11-11 17:51:38 +02:00
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// Execute `rustlings hint iterators4` for hints.
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2017-01-06 05:38:07 +02:00
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}
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#[cfg(test)]
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mod tests {
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use super::*;
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2022-01-13 23:11:52 +02:00
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#[test]
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fn factorial_of_0() {
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assert_eq!(1, factorial(0));
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}
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2017-01-06 05:38:07 +02:00
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#[test]
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fn factorial_of_1() {
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assert_eq!(1, factorial(1));
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}
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#[test]
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fn factorial_of_2() {
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assert_eq!(2, factorial(2));
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}
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#[test]
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fn factorial_of_4() {
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assert_eq!(24, factorial(4));
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}
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}
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