Submission #1219509

#	Time	Username	Problem	Language	Result	Execution time	Memory
1219509		giorgi123glm	별들과 삼각형 (IZhO11_triangle)	C++20	100 / 100	294 ms	5856 KiB

triangle

#include <algorithm>
#include <functional>
#include <iostream>
#include <list>
#include <map>
using namespace std;

signed main () {
    ios::sync_with_stdio (false);
    cin.tie (0);
    cout.tie (0);

    int N = 0;
    cin >> N;
    vector <pair <int, int> > v (N + 1);
    for (int i = 1; i <= N; i++)
        cin >> v[i].first >> v[i].second;

    map <int, int> byY;
    map <int, int> byX;
    for (int i = 1; i <= N; i++) {
        byY[v[i].first]++;
        byX[v[i].second]++;
    }

    long long ans = 0;
    for (int i = 1; i <= N; i++)
        ans += 1ll * (byY[v[i].first] - 1) * (byX[v[i].second] - 1);
    cout << ans << '\n';
}

• Subtask 1: 100 / 100