24点游戏算法

def solve(____):
    def calc24(____):
        if len(____) == ____:
            return abs(____) < 1e-____
        for i in range(len(____)):
            for j in range(len(____)):
                if i == j: continue
                rest = [nums[k] for k in range(len(____)) if k != i and k != j]
                a, b = nums[i], nums[j]
                nexts = [a+b, a-b, a*b]
                if b != ____: nexts.append(____)
                for c in nexts:
                    if calc24(____):
                        return True
        return False
    nums = list(map(float, str(____).strip().split(____)))
    print('____' if calc24(____) else '____')