371. Sum of Two Integers

https://leetcode.com/problems/sum-of-two-integers/

Python

• Use operator module for better understand

from operator import xor, invert, and_


class Solution:
    def getSum(self, a: int, b: int) -> int:
        x, y = abs(a), abs(b)

        # Ensure x >= y
        if x < y:
            return self.getSum(b, a)

        sign = 1 if a > 0 else -1

        if a * b >= 0:
            # a and b are possitive integers
            while y:
                x, y = xor(x, y), and_(x, y) << 1
        else:
            while y:
                x, y = xor(x, y), and_(invert(x), y) << 1

        return sign * x

Javascript

var getSum = function(a, b) {
    while (b != 0){
        const c = a & b;
        a = a^b;
        b = c << 1;
    }
    return a;
};