sort test

#include <iostream>
#include <random>
#include <algorithm>
#include <chrono>

using namespace std;



class timer{
    std::chrono::time_point<std::chrono::high_resolution_clock> a,b;
public:
    void start(){a = std::chrono::high_resolution_clock::now();}
    void stop() {b = std::chrono::high_resolution_clock::now();}
    double value()
    {
        std::chrono::duration<double> elapsed_seconds = b-a;
        return elapsed_seconds.count();
    }
};

int main()
{
    const size_t N = 120'000'000;
    vector<uint64_t> tab;
    random_device rd;
    mt19937_64 gen(rd());

    uniform_int_distribution<uint64_t> dist(0);


    for (int i=0; i<5; i++){
        generate_n(back_inserter(tab), N, [&](){ return  dist(gen) ; } ) ;
        timer st;
        st.start();
        sort(begin(tab),end(tab));
        st.stop();
        cout<<tab[3]<<endl; //do not optimize the array out, please
        cout<<is_sorted(begin(tab),end(tab))<<endl;
        cout<<st.value()*1000<<" ms"<<endl;
        tab.clear();
    }
    return 0;
}