Leetcode - 371. Sum of Two Integers

题设：

Calculate the sum of two integers a and b, but you are not allowed to use the operator + and -.

解题思路：

使用加法器

代码：

class Solution:
    def getSum(self, num1, num2):
        if (num2 == 0):
            return num1
        sum = num1 ^ num2
        carry = (num1 & num2) << 1
        return self.getSum(sum,carry)

结果：

python本地运行：通过

run code运行：通过，运行时间32ms

submit结果：不通过，报“超出内存限制”