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62 lines
927 B
Rust
62 lines
927 B
Rust
// iterators4.rs
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pub fn factorial(num: u64) -> u64 {
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// Complete this function to return factorial of num
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// Do not use:
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// - return
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// For extra fun don't use:
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// - imperative style loops (for, while)
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// - additional variables
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// For the most fun don't use:
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// - recursion
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// Scroll down for hints.
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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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#[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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// In an imperative language you might write a for loop to iterate through
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// multiply the values into a mutable variable. Or you might write code more
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// functionally with recursion and a match clause. But you can also use ranges
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// and iterators to solve this in rust.
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