// Guide to Java
// Copyright 2014, by J.T. Streib and T. Soma


import java.util.*;

class Gcd {
 // method to compute greatest common divisor
 private static int gcd(int num1, int num2) {
    if(num2 >= 1)
       return gcd(num2, num1%num2);
    else
       return num1;
 }

 public static void main(String[] args) {
    // declaration and initialization of variables
    int n, k, result;
    Scanner scanner = new Scanner(System.in);
    
    // input two integers
    System.out.print("Enter first number: ");
    n = scanner.nextInt();
    System.out.print("Enter second number: ");
    k = scanner.nextInt();
    
    // compute greatest common divisor
    result = gcd(n, k);
    
    // output greatest common divisor
    System.out.println();
    System.out.println("The greatest common divisor of " + n
                        + " and " + k + " is " + result + ".");
 }
}