int program (int argc, string[] argv) {
  var x = new int[][]{new int[]{1},
                      new int[]{2},
                      new int[]{3},
                      new int[]{4}};
  var ans = 0;

  for(var i=0;i<4;i=i+1;) {
    ans = x[i][0] - ans;
  }

  if((5 [&] ~5 [|] 0) != 0) {
    return ans;
  } else {
    return -ans;
  }

  return ans;
}