int loop = 3000000;
unsigned long long test=0b10000;
int expected = 1;

void test1() {
auto start_time = std::chrono::high_resolution_clock::now();
    for(int x=0;x < loop;x++) {
        unsigned long long t=test;
        int z = 0;
        while(t)
        {
            if(t&1) z++;
            t=t>>1;
        }
        if(z!=expected) {
            cerr<<"error"<<endl;
        }
    }
    auto end_time = std::chrono::high_resolution_clock::now();
     auto time = end_time - start_time;
    cerr << time/std::chrono::milliseconds(1) << "ms to run.\n";
}

void test2() {
     auto start_time = std::chrono::high_resolution_clock::now();
    for(int x=0;x < loop;x++) {
        unsigned long long t=test;
        int z = 0;
        for(int i; t; t=t^1ULL<<i)
        {
            i=__builtin_ctzll(t);
            z++;
        }
        if(z!=expected) {
            cerr<<"error"<<endl;
        }
    }
    auto end_time = std::chrono::high_resolution_clock::now();
     auto time = end_time - start_time;
    cerr << time/std::chrono::milliseconds(1) << "ms to run.\n";
}

void test3() {
     auto start_time = std::chrono::high_resolution_clock::now();
    for(int x=0;x < loop;x++) {
        unsigned long long t=test;
        int z = 0;
        for(int i=0; t; t=t>>(i+1))
        {
            i=__builtin_ctzll(t);
            z++;
        }
        if(z!=expected) {
            cerr<<"error"<<endl;
        }
    }
    auto end_time = std::chrono::high_resolution_clock::now();
     auto time = end_time - start_time;
    cerr << time/std::chrono::milliseconds(1) << "ms to run.\n";
}