def f(nums,target): if (len(nums) == 1): return nums[0] == target for i in range(len(nums)): c = nums[i] # 当前数字 tmp = nums[:i] + nums[i+1:] # 列表中的其他数字 if f(tmp,target+c) or f(tmp,target-c) or f(tmp,target*c) or f(tmp,target/c): return True ret...