题解 | #24点游戏算法#

def dfs(L, res=0):
    if len(L) == 0:
        if int(res + 0.999) == 24 and int(res) == 24:
            return True
        else:
            return False
    if len(L) == 4:
        for i in range(len(L)):
            n = L[i]
            del L[i]
            if dfs(L, res + n):
                return True
            L.append(n)
    for i in range(len(L)):
        for op in "+-*/":
            n = L[i]
            del L[i]
            if op == "+":
                if dfs(L, res + n):
                    return True
            elif op == "-":
                if dfs(L, res - n):
                    return True
            elif op == "*":
                if dfs(L, res * n):
                    return True
            elif op == "/":
                if dfs(L, res / n):
                    return True
            L.append(n)


L = list(map(int, input().split()))
if dfs(L):
    print("true")
else:
    print("false")