Poistot

#include<bits/stdc++.h>
using namespace std;
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define fi first
#define se second
#define pii pair<int,int>
using ll = long long;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n;
    cin >> n;

    vector<vector<int>> v;
    for (int i = 1; i <= n; i++) {
        int x;
        cin >> x;
        if (v.empty()) {
            v.push_back({x});
            continue;
        }
        int l = 0, r = v.size()-1;
        while (l < r) {
            int k = (l+r)/2;
            if (v[k].back() < x) r = k;
            else l = k+1;
        }
        if (v[l].back() < x) v[l].push_back(x);
        else v.push_back({x});
    }

    cout << v.size() << "\n";
    for (auto u : v) {
        for (int x : u) cout << x << " ";
        cout << "\n";
    }
    
    return 0;
}

/*

x = 6

15 11 8 7 7 4 1
          l r  


*/

Test 1

Group: 1, 3

Verdict: ACCEPTED

Test 2

Group: 1, 2, 3

Verdict: ACCEPTED

Test 3

Group: 1, 3

Verdict: ACCEPTED

Test 4

Group: 1, 3

Verdict: ACCEPTED

Test 5

Group: 2, 3

Verdict: ACCEPTED

Test 6

Group: 2, 3

Verdict: ACCEPTED

Test 7

Group: 3

Verdict: ACCEPTED

Test 8

Group: 3

Verdict: ACCEPTED

Test 9

Group: 3

Verdict: ACCEPTED

Test 10

Group: 3

Verdict: ACCEPTED