Java 代码

import java.util.Scanner;

public class Main
{
    public static int gcd (int m, int n)
    {
        // swap without using temp 
        if (m < n)
        {
            m = m - n;
            n = m + n; // n is m now
            m = n - m; // m is n now
        }

        if ( m % n == 0)
            return n;

        return gcd (n, m % n );
    }

    public static void main(String[] args)
    {
        Scanner cin = new Scanner(System.in);

        int m = cin.nextInt();
        int n = cin.nextInt();

        System.out.println (gcd (m, n));
    }
}