#暴力法的修改,可以满足2 5 2 7 import itertools def appends(lst,a,b): lst.append(a+b) lst.append(a-b) lst.append(a*b) if b != 0: lst.append(a/b) return lst def solution(a,b,c,d): for nums in itertools.permutations([a,b,c,d]): a,b,c,d = nums lst16 = [] lst64 = [] lst4 = appends([],a,b) lst8 = appends([],c,d) fo...