import itertools def compute(s1_list,s2): out = [] for cmp in ['+','-','*','/']: for s1 in s1_list: out.append('('+s1+cmp+s2+')') return out a,b,c,d = input().split() #取两个运算 compute_s = [] for x1,x2,x3,x4 in itertools.permutations([a,b,c,d]): temp = compute(...