1619 - Restaurant Customers

using namespace std;
using ii = pair<int, int>;
using vii = vector<ii>;
int main(void)
{
    int n, a, b, people = 0, ans = 0;
    cin >> n;
    vii events(2 * n);
    for (int i = 0; i < n; ++i)
    {
        cin >> a >> b;
        events[2 * i] = {a, +1};
        events[2 * i + 1] = {b, -1};
    }
    sort(events.begin(), events.end());
    for (auto [t, s] : events)
    {
        people += s;
        ans = max(ans, people);
    }
    cout << ans << endl;
    return 0;
}