39 lines
852 B
Rust
39 lines
852 B
Rust
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// vec2.rs
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// A Vec of even numbers is given. Your task is to complete the loop
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// so that each number in the Vec is multiplied by 2.
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//
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// Make me pass the test!
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//
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// Execute the command `rustlings hint collections2` if you need
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// hints.
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// I AM NOT DONE
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fn vec_loop(mut v: Vec<i32>) -> Vec<i32> {
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for i in v.iter_mut() {
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// TODO: Fill this up so that each element in the Vec `v` is
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// multiplied by 2.
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}
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// At this point, `v` should be equal to [4, 8, 12, 16, 20].
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v
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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 test_vec_loop() {
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let v: Vec<i32> = (1..).filter(|x| x % 2 == 0).take(5).collect();
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let ans = vec_loop(v.clone());
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assert_eq!(
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ans,
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v.iter()
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.map(|x| x * 2)
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.collect::<Vec<i32>>()
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);
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}
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}
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