Test định dạng code C++

``` cpp
#include <iostream>
#include <fstream>
#include <vector>
#include <algorithm>

using namespace std;

// Ham so sanh ti le gia tri tren khoi luong giam dan
bool getSosanhtile(const pair<int, int>& a, const pair<int, int>& b)
{
    return (double)a.first / a.second > (double)b.first / b.second;
}

// Ham rut gon phan so
pair<int, int> getRutgonphanso(int tuso, int mauso)
{
    int gcd = __gcd(tuso, mauso);
    return {tuso / gcd, mauso / gcd};
}

int main()
{
    ifstream fin("DIAMOND.inp");
    int N, K;
    fin >> N >> K;

    vector<int> vGiatri(N);  // Mang luu gia tri cua cac vien kim cuong
    vector<int> vKhoiluong(N); // Mang luu khoi luong cua cac vien kim cuong
    for (int i = 0; i < N; ++i)
    {
        fin >> vGiatri[i] >> vKhoiluong[i];
    }
    fin.close();

    // Tao mot vector cac cap gia tri, khoi luong
    vector<pair<int, int>> capgiatrikhoiluong;
    for (int i = 0; i < N; ++i)
    {
        capgiatrikhoiluong.push_back({vGiatri[i], vKhoiluong[i]});
    }

    // Sap xep cac vien kim cuong theo ti le gia tri tren khoi luong giam dan
    sort(capgiatrikhoiluong.begin(), capgiatrikhoiluong.end(), getSosanhtile);

    // Chon ra K vien kim cuong co ti le gia tri tren khoi luong lon nhat
    int tonggiatri = 0;
    int tongkhoiluong = 0;
    for (int i = 0; i < K; ++i)
    {
        tonggiatri += capgiatrikhoiluong[i].first;
        tongkhoiluong += capgiatrikhoiluong[i].second;
    }

    // Rut gon phan so cua tong gia tri tren tong khoi luong
    pair<int, int> getRutgon = getRutgonphanso(tonggiatri, tongkhoiluong);

    // Ghi ket qua vao file output
    ofstream fout("DIAMOND.out");
    fout << getRutgon.first << " " << getRutgon.second << endl;
    fout.close();

    return 0;
}