Сложить 2 дроби

#include <iostream>
using int64 = int64_t;
using namespace std;
int64 gcd(int64 a, int64 b){
    while (a != 0 && b != 0){
        if (a < b){
            swap(a, b);
        }
        a = a % b;
    }
    return b;
}
int main(){
    int64 a, b, c, d;
    cin >> a >> b >> c >> d;
    int GCD = gcd(d, b);
    int lcm = d * b/GCD;
    int num = (a*d + c*b)/GCD;
    int t = gcd(num, lcm);
    cout << num/t << " " << lcm/t;
    return 0;
}