The plus and minus keys of a calculator are broken. The bit keys (AND, OR, XOR and shifts) still work.
Given two whole numbers a and b, return their sum. In your code, do not use the operators + and -. Use bit operations instead.
Examples
Example 1:
Input: a = 17, b = 26
Output: 43
Explanation: 17 + 26 = 43.
Example 2:
Input: a = -30, b = 12
Output: -18
Explanation: One number is negative, so the sum is smaller than the positive one.
Example 3:
Input: a = -250, b = -750
Output: -1000
Explanation: Both numbers are negative, so the sum is negative too.