Values and decisions

15-minute session: read for 3 minutes, trace for 3, experiment for 7, and complete the check for 2. Spend longer whenever you need.

A decision chooses which statements run. The policy here is “ready at 80 or higher.” Trace 85, 79, 80, and 81 before running each case. The comparison includes 80. A program that prints the right answer for 85 may still be wrong at the boundary. Add a separate check rejecting scores below 0 or above 100; rejection and needing practice mean different things.

fn main is the entry point. let introduces a binding; mut permits reassignment. println! is a macro. A reference such as &plan borrows rather than transfers ownership.


fn main() {
    let score = 85;
    if score >= 80 { println!("Ready"); } else { println!("Practice"); }
}

Expected result: Ready

Practice and evidence

Keep three notes: your prediction, the actual result, and why they match or differ. The completion check grades understanding; the practice task builds skill.

Language reference