implement a plus b / a minus b without using any arithmetic operators
class Solution: """ @param a: An integer @param b: An integer @return: The sum of a and b """ def aplusb(self, a, b): # write your code here if b == 0: return a s = a ^ b carry = (a & b) << 1 return self.aplusb(s, carry) # a ^ b 得当前位的和 # (a & b) 得当前位的进位 # 当计算下一对二进制位的元素时,需要将当前进位左移一位 # def aminusb(self, a, b): # # a - b # # a + (-b) # # -b = ~b + 1 # return self.aplusb(a, aplusb(~b, 1))