Common Denominators

• Time : $O(log(fraction))$
• Space : $O(1)$

using namespace std;
class Fracts
{
    static string frac(unsigned long long n, unsigned long long d) {
        return "(" + to_string(n) + "," + to_string(d) + ")";
    }
public:
    static std::string convertFrac(std::vector<std::vector<unsigned long long>> &lst) {
        unsigned long long lcm = lst[0][1];
        for(auto fraction : lst) {
            unsigned long long g = __gcd(fraction[1], lcm);
            lcm = lcm / g * fraction[1];
        }
        string res = "";
        for(auto& fraction : lst) {
            unsigned long long x = lcm / fraction[1];
            res += frac(fraction[0] * x, lcm);
        }
        return res;
    }
};