Discussion on: Daily Challenge #141 - Two Sum

fn two_sum(numbers: &[i64], target: i64) -> Option<(usize, usize)> {
    let mut complete_with = std::collections::HashMap::new();
    for (idx1, &num) in numbers.iter().enumerate() {
        if let Some(&idx2) = complete_with.get(&(target - num)) {
            return Some((idx1, idx2));
        } else {
            complete_with.insert(num, idx1);
        }
    }
    None
}

fn main() {
    for (numbers, target) in &[
        (vec![1234, 5678, 9012], 14690),
        (vec![1, 2, 3], 4),
        (vec![2, 2, 3], 4),
        (vec![5, 10, 15, 20, 25, 30], 50),
    ] {
        if let Some((idx1, idx2)) = two_sum(numbers, *target) {
            assert!(numbers[idx1] + numbers[idx2] == *target);
        }
    }
}