mirror of
https://github.com/rust-lang/rustlings.git
synced 2024-12-29 00:36:30 +00:00
42 lines
896 B
Rust
42 lines
896 B
Rust
// iterators4.rs
|
|
//
|
|
// Execute `rustlings hint iterators4` or use the `hint` watch subcommand for a
|
|
// hint.
|
|
|
|
// I AM NOT DONE
|
|
|
|
pub fn factorial(num: u64) -> u64 {
|
|
// Complete this function to return the factorial of num
|
|
// Do not use:
|
|
// - early returns (using the `return` keyword explicitly)
|
|
// Try not to use:
|
|
// - imperative style loops (for, while)
|
|
// - additional variables
|
|
// For an extra challenge, don't use:
|
|
// - recursion
|
|
// Execute `rustlings hint iterators4` for hints.
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
|
|
#[test]
|
|
fn factorial_of_0() {
|
|
assert_eq!(1, factorial(0));
|
|
}
|
|
|
|
#[test]
|
|
fn factorial_of_1() {
|
|
assert_eq!(1, factorial(1));
|
|
}
|
|
#[test]
|
|
fn factorial_of_2() {
|
|
assert_eq!(2, factorial(2));
|
|
}
|
|
|
|
#[test]
|
|
fn factorial_of_4() {
|
|
assert_eq!(24, factorial(4));
|
|
}
|
|
}
|