You are given two integer values a and b. Your task is to compute their arithmetic sum and return the result. However, your solution must not use the addition (+) or subtraction (-) operators anywhere in the code.
Both numbers should be treated as 32-bit signed integers. The range of the inputs guarantees that the correct sum will always be representable within that 32-bit signed integer limit.
Example 1
Input: a = 4, b = 9
Output: 13
Example 2
Input: a = -7, b = 3
Output: -4
Explanation: Because the operands have opposite signs, the carry propagation must work correctly under two's complement representation.
Example 3
Input: a = 0, b = -5
Output: -5
-1000 <= a, b <= 1000