wtfsort c++

#include <string>
#include <algorithm>
#include <iostream>
#include <vector>
#include <random>

using namespace std;

int main(){

    const size_t N = 5000;
    vector<int> tab(N);

    random_device rd;
    mt19937_64 gen(rd());
    uniform_int_distribution<int> dist;
    generate(begin(tab),end(tab), [&](){return dist(gen);} );


    for (auto &a: tab)
        for (auto &b: tab)
            if (a < b) swap(a,b);


    if (is_sorted(begin(tab), end(tab)))
        cout<<"sorted\n";
    else cout<<"blah\n";

}