for (y = 1; y <= Bottom; y++) {
  x = 2;
  while ([x,y] != "") {
    x++;
  }
  while ([1,y+1] == [1,y]) {
    for (xx = 2; xx <= Right; xx++) {
      if ([xx,y+1] != "") {
        [x,y] = [xx,y+1];
        x++;
      }
    }
    DeleteRow(y + 1);
  }
}