用python38写一份可以输入数字的24点游戏算法的程序

下面是一个使用Python 3.8编写的可以输入数字的24点游戏算法程序的示例：

from itertools import permutations, product

def evaluate(exp):
    # 运算符优先级
    precedence = {'+': 1, '-': 1, '*': 2, '/': 2}
    # 运算符栈和操作数栈
    op_stack = []
    num_stack = []

    for token in exp:
        if token.isdigit():
            num_stack.append(int(token))
        else:
            while op_stack and precedence[op_stack[-1]] >= precedence[token]:
                op = op_stack.pop()
                num2 = num_stack.pop()
                num1 = num_stack.pop()
                if op == '+':
                    result = num1 + num2
                elif op == '-':
                    result = num1 - num2
                elif op == '*':
                    result = num1 * num2
                elif op == '/':
                    result = num1 / num2
                num_stack.append(result)
            op_stack.append(token)

    while op_stack:
        op = op_stack.pop()
        num2 = num_stack.pop()
        num1 = num_stack.pop()
        if op == '+':
            result = num1 + num2
        elif op == '-':
            result = num1 - num2
        elif op == '*':
            result = num1 * num2
        elif op == '/':
            result = num1 / num2
        num_stack.append(result)

    return num_stack[0]

def solve_24(nums):
    ops = ['+', '-', '*', '/']
    for perm in permutations(nums):
        for op1, op2, op3 in product(ops, repeat=3):
            exp = [str(perm[0]), op1, str(perm[1]), op2, str(perm[2]), op3, str(perm[3])]
            if evaluate(exp) == 24:
                return exp
    return None

# 输入四个数字
nums = [int(input(f"请输入第{i+1}个数字: ")) for i in range(4)]

solution = solve_24(nums)
if solution:
    print("找到解：", ' '.join(solution), "= 24")
else:
    print("无解")

这个程序使用了迭代器permutations和product来生成数字和运算符的所有排列和组合，然后通过逆波兰表达式的计算方式来计算表达式的值。最后，程序会输出解（如果存在）或者无解的信息