Longest Strictly Increasing Subsequence

#include <bits/stdc++.h>

using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    cout.tie(nullptr);
    int T;
    cin >> T;
    while(T--) {
        int N;
        cin >> N;
        vector < int > a(N), deck;
        for(int& x : a)
            cin >> x;
        for(int x : a) {
            if(deck.empty()) {
                deck.emplace_back(x);
                continue;
            }
            if(x > deck.back()) {
                deck.emplace_back(x);
                continue;
            }
            auto it = lower_bound(deck.begin(), deck.end(), x);
            *it = x;
        }
        cout << deck.size() << '\n';
    }
}