projecteuler.net/004/main.rs

fn is_polindrome(n: i32) -> bool {
    let s = n.to_string();
    for (p, q) in s.chars().zip(s.chars().rev()) {
        if q != p { return false; }
    }
    return true;
}

fn main() {
    let n = 999;
    let mut best_i = 1;
    let mut best_j = 1;
    let mut best_poli = 1;
    for i in 100..=n {
        for j in 100..=n {
            let m = i * j;
            if is_polindrome(m) {
                if m > best_poli {
                    best_poli = m;
                    best_i = i;
                    best_j = j;
                }
            }
        }
    }
    println!("{}*{}={}", best_i, best_j, best_poli);
}