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Core Beginner

00 Variables

Rust bindings are immutable unless you say otherwise, and constants carry an explicit type.

Step 1 / 3

Make total mutable so with_bonus can add the bonus and return the new score.

Hints

let is immutable by default -- add mut to reassign.

00_variables.rs

// with_bonus should add the bonus and return the new score.
// A plain `let` binding can't be reassigned -- make it mutable.
fn with_bonus(score: i32, bonus: i32) -> i32 {
    let total = score;
    // total = total + bonus;   // <- uncomment and make it compile
    total
}

// with_bonus should add the bonus and return the new score.
// A plain `let` binding can't be reassigned -- make it mutable.
fn with_bonus(score: i32, bonus: i32) -> i32 {
    let total = score;
    // total = total + bonus;   // <- uncomment and make it compile
    total
}

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

Reveal solution

fn with_bonus(score: i32, bonus: i32) -> i32 {
    let mut total = score;
    total = total + bonus;
    total
}

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00 Variables