/* This program is free software; you can redistribute it and/or modify it under  
 * the terms of the GNU General Public License as published by the Free Software  
 * Foundation; either version 2 of the License, or (at your option) any later     
 * version.                                                                       
 *                                                                                  
 * This program is distributed in the hope that it will be useful, but WITHOUT    
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS  
 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. 
 * 
 * Calculate the GCD of two numbers.
 *
 */

{
   int x, y;
   int tmp;
   int gcd;

   y = 48128;  // 47 * 1024
   x = 6439;   // 47 * 137

   // the rest of the code is parametric on x and y   

   // make sure x is the bigger of the two
   if (x < y) { tmp = x; x = y; y = tmp; }

   writeint x;
   writeint y;

   // as long as both numbers are larger than 1,
   while (y > 1) {
     x %= y;   

     if (x == 0) break;
     else { // gcd (x, y) = gcd (y, x % y).
        tmp = x; x = y; y = tmp;
     }
   }

   gcd = y;

   // print it out
   writeint gcd;
}