fn mcd(a: i32, b: i32) -> i32
{
    if a % b != 0 {
        mcd(b, a % b)
    } else {
        b
    }
}

fn main()
{
    let a = 66;
    let b = 12;
    let m = mcd(a, b);

    println!("mcd({},{})={}", a, b, m);
}