And don't really think this is an easy question. Took me almost 15 mins.

```
public class Solution {
public int getSum(int a, int b) {
int m = (a&b) << 1 ;
int n = a^b;
while ((m&n)!=0){
int t = (m&n) << 1 ;
int s = m^n;
m = t;
n = s;
}
return m|n;
}
}
```