private void HorizontalCouple(int y, int x, Puzzle[,] puzzles)
 {
     if (x != puzzles.GetLength(1) - 1 && puzzles[y, x + 1] != null)
     {
         puzzles[y, x].Changed = true;
         puzzles[y, x].Width *= 2;
         puzzles[y, x + 1] = null;
     }
 }
 private void VerticalCouple(int y, int x, Puzzle[,] puzzles)
 {
     if (y != puzzles.GetLength(0) - 1)
     {
         puzzles[y, x].Changed = true;
         puzzles[y, x].Height *= 2;
         puzzles[y + 1, x] = null;
     }
 }