371. Sum of Two Integers

Return the sum of integers a and b without using the + or − operators.

a ^ b adds without carrying; (a & b) << 1 is the carry. Repeat until there is no carry left.

1function getSum(a: number, b: number): number {
2  while (b !== 0) {
3    const carry = (a & b) << 1;
4    a = a ^ b;
5    b = carry;
6  }
7  return a;
8}

a = 5b = 7

a

b

b = 7 ≠ 0, so there is still something to add.

1 / 0

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