SlidingPuzzlewithStandardPythonModulesandwithoutClass

滑动拼图是一种常见的游戏，本教程将通过 Python 标准模块来实现无类的滑动拼图游戏。

在开始之前，需要导入以下 Python 标准模块：

import random
from copy import deepcopy

接下来，定义行和列的数量以及横向和纵向的偏移量：

ROWS = 4
COLS = 4

DX = [0, 0, 1, -1]
DY = [1, -1, 0, 0]

定义初始和结束状态：

INIT_STATE = [[1,2,3,4],
              [5,6,7,8],
              [9,10,11,12],
              [13,14,15,0]]

GOAL_STATE = [[0,1,2,3],
              [4,5,6,7],
              [8,9,10,11],
              [12,13,14,15]]

接着，定义移动函数：

def move(state, x, y, nx, ny):
    new_state = deepcopy(state)
    new_state[x][y], new_state[nx][ny] = new_state[nx][ny], new_state[x][y]
    return new_state

然后，定义启发函数：

def heuristic(state):
    res = 0
    for i in range(ROWS):
        for j in range(COLS):
            if state[i][j] == 0:
                continue
            x, y = (state[i][j]-1) // COLS, (state[i][j]-1) % COLS
            res += abs(x-i) + abs(y-j)
    return res

接下来，定义主函数：

def main():
    state = INIT_STATE
    steps = []
    steps.append(state)
    while state != GOAL_STATE:
        candidates = []
        x, y = 0, 0
        for i in range(ROWS):
            for j in range(COLS):
                if state[i][j] == 0:
                    x, y = i, j
                    break
            if state[i][j] == 0:
                break
        
        for i in range(4):
            nx, ny = x+DX[i], y+DY[i]
            if 0 <= nx < ROWS and 0 <= ny < COLS:
                new_state =