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Core Beginner

05 Collections

Work with the two collections you'll reach for most: find a maximum safely, then tally word frequencies.

Step 1 / 2

Return the largest element, or None if empty, in max.

Hints

05_collections.rs

// largest element, or None if empty
fn max(v: &[i32]) -> Option<i32> {
    todo!()
}

// largest element, or None if empty
fn max(v: &[i32]) -> Option<i32> {
    todo!()
}

Reset to starterCompiled in a sandbox; hidden checks must pass.

Reveal solution

fn max(v: &[i32]) -> Option<i32> {
    v.iter().copied().max()
}