inline void solve() {
    init();
    vector<int> q = {1, 2, 3, 4, 5};
    cout << *lower_bound(q.begin(), q.end(), 3) << '\n'; // first >=
    cout << *upper_bound(q.begin(), q.end(), 4) << '\n'; // first >
    cout << *(upper_bound(q.begin(), q.end(), 1) - 1) << '\n'; // last <=
    cout << *(lower_bound(q.begin(), q.end(), 2) - 1) << '\n'; // last <
    cout << *upper_bound(q.rbegin(), q.rend(), 3, [](int a, int b){  //last <, but another words
        return a > b;
    }) << '\n';
}

/*
output
3
5
1
1
2
*/