拼图的目标是在大约滑动瓦下令从1到8瓦
8 puzzle is played on a 3-by-3 grid with 8 square blocks labeled 1 through 8 and a blank square. Your goal is to rearrange the blocks so that they are in order, using as few moves as possible. You are only allowed to slide a block horizontally or vertically into the blank square.