Binge watching

#include <bits/stdc++.h>
using namespace std;

using ll = long long;

int N = 1000'000'000-1;

void solve() {
    int n;
    cin >> n;

    map<int, int> movies;
    int a, b;
    for(int i = 0; i < n; i++) {
        cin >> a >> b;
        movies[a] = movies.count(a) == 1 ? min(movies[a], b) : b;
    }

//     for(const auto elem : movies)
// {
//    std::cout << elem.first << " " << elem.second <<"\n";
// }

    int m = 1;
    movies[N] = 0;
    for (auto it = ++movies.rbegin(); it != movies.rend(); ++it) {
        auto next = movies.lower_bound(it->second);

        // if (next != movies.end()) {
            it->second = next->second + 1;
        // } else {
        //     it->second = 1;
        // }

        // cout << "k " << it->first << " " << it->second << "\n";

        m = max(m, it->second);
    }
// cout << "---";
//     for(const auto elem : movies)
// {
//    std::cout << elem.first << " " << elem.second <<"\n";
// }

    cout << m << endl;
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);

    solve();

    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: WRONG ANSWER

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: WRONG ANSWER

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED