Stdle #95 · option · 2026-09-09

What does this Rust snippet output?

A past puzzle — fully playable. 4 attempts, hints on wrong guesses.

1fn main() {
2    let nums = [Some(1), None, Some(3)];
3    let total: i32 = nums.iter()
4        .flatten()
5        .sum();
6    println!("{}", total);
7}

Option

What does this Rust snippet output?

Answer & explanation