371. Sum of Two Integers

Problem description

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

Example:

Given a = 1 and b = 2, return 3.

题目描述

计算两个整数a与b的和，但是你不能使用+、－运算

例子

输入a = 1，b = 2，返回3

链接：https://leetcode.com/problems/sum-of-two-integers/

解题思路

模拟计算机二进制形式的计算加法，采用异或、与、移位运算

public class Solution {    public int getSum(int a, int b) {        int c = a ^ b;int d = (a & b) << 1;while(d != 0){a = d;b = c;c = a ^ b;d = (a & b) << 1; }return c;    }}

此外java还自带的Math.addExact(a, b)函数，python的sum()函数都可以用来ac这道题，不过不是正途。