Python之计算24点

╰半橙微兮° 2022-06-06 09:16 225阅读 0赞

完整的代码如下：

# -*- coding: utf-8 -*-
    import itertools
    
    #with brackets
    def with_brackets(lst, ops_lst):
        for op in ops_lst: #无括号时的运算情形
            expr1 = '('+lst[0]+op[0]+lst[1]+')'+op[1]+lst[2]+op[2]+lst[3]
            expr2 = '('+lst[0]+op[0]+lst[1]+op[1]+lst[2]+')'+op[2]+lst[3]
            expr3 = lst[0]+op[0]+'('+lst[1]+op[1]+lst[2]+')'+op[2]+lst[3]
            expr4 = '('+lst[0]+op[0]+lst[1]+')'+op[1]+'('+lst[2]+op[2]+lst[3]+')'
    
            for expr in [expr1, expr2, expr3, expr4]:
                try:
                    t=eval(expr)
                except: #作除法时，跳过分母为0时的情形
                    pass
    
                if abs(t-24) < 0.001:#float型数值计算存在微小的误差
                    return expr
        return 0
    
    #返回4个数计算24的方法
    def hasMethod(numbers, ops_lst):
        for lst in itertools.permutations(numbers):
            lst = list(map(lambda x:str(x), lst))
            #without brackets
            for op in ops_lst:
                expr = lst[0]+op[0]+lst[1]+op[1]+lst[2]+op[2]+lst[3]
                if abs(eval(expr)-24) < 0.001:
                    return expr
            #with brackets
            expr = with_brackets(lst, ops_lst)
            if expr != 0:
                return expr
    
        return 0
    
    #返回4个数计算24的方法，无方法时返回"No Method"
    def cal_24(numbers):
        ops = ['+','-','*','/']
        ops_lst = [[i,j,k] for i in ops for j in ops for k in ops]
    
        expr = hasMethod(numbers, ops_lst)
        if expr != 0:
            return expr
        else:
            return 'No method!'
    
    #所有情况的计算24点的办法，并输出到文本文件
    def main():
    
        outfile=open("H:\\24dian.txt","w")
        numbers_lst = [[i,j,k,l] for i in range(1,14) for j in range(1,14)\
                                 for k in range(1,14) for l in range(1,14)]
    
        for numbers in numbers_lst:
            a = list(map(lambda x: str(x), numbers))
            methodInfo = "[%s,%s,%s,%s]: %s\n"%(a[0],a[1],a[2],a[3],cal_24(numbers))
            outfile.write(methodInfo)
    
        outfile.close()    
    
    main()

输出的文件如下：  
![这里写图片描述][SouthEast]  
所有的情况可查看文件：[https://gitee.com/Jclian91/24DianJiJiSuan][https_gitee.com_Jclian91_24DianJiJiSuan]

--------------------

本次分享到此结束，欢迎大家交流与批评~~

[SouthEast]: /images/20220606/6d8ed031f31841d083a272df0f798c9d.png
[https_gitee.com_Jclian91_24DianJiJiSuan]: https://gitee.com/Jclian91/24DianJiJiSuan