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.
Credits:
Special thanks to @fujiaozhu for adding this problem and creating all test cases.
1 public class Solution { 2 public int getSum(int a, int b) { 3 int sum = a^b;//保留二进制和中两位不相同的位 4 int carry = a&b;//保留二进制中两个都为1 的位置 5 int tmp = 0; 6 while(carry != 0){ 7 carry = carry << 1;// 通过移位来循环计算，将值加上 8 tmp = sum; 9 sum ^= carry; 10 carry &= tmp; 11 } 12 return sum; 13 } 14 }
这是leetcode 比较新的一题，挺有意思的。