Add and subtract ints in C++ without using + or - operators.

binadd.cpp

#include <iostream>
// not sure why i included this but now i will just leave it here. yolo
#include <string>

// add a and b
int binadd(int a, int b) {
	int carry = (a & b) << 1;
	int result = a ^ b;
	if (carry == 0)
		return result;
	else
		result = binadd(result, carry);

	return result;
}

// subtract b from a
int binsub(int a, int b) {
	// binadd(~b, 1) = two's complement of b, AKA -b
	return binadd(a, binadd(~b, 1));
}

int main(int argc, char* argv[]) {
	std::cout << binadd(5, 1) << std::endl;
	std::cout << binadd(12, 12) << std::endl;
	std::cout << binsub(5, 1) << std::endl;
	std::cout << binsub(12, 12) << std::endl;
	return 0;
}