leetcode 371.Sum of Two Integers

题目

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.

难度： Easy

实现

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