int gcd(int a, int b) {
  while (b != 0) {
    var t = b;
    b = mod(a, b);
    a = t;
  }

  return a;
}

int mod (int a, int b) {
  
  var t = a;
  while (t - b >= 0) {
      t = t - b;
  }

  return t;
}

int program (int argc, string[] argv) {
  var a = 64;
  var b = 48;

  return gcd(a, b);
}