Submission #887998

#	Time	Username	Problem	Language	Result	Execution time	Memory
887998		gnu	Star triangles (IZhO11_triangle)	C++17	100 / 100	271 ms	15028 KiB

triangle

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
void solve()
{
//    ifstream fin("triangles.in");
//    ofstream fout("triangles.out");
    int n; cin >> n;
    map<int, int> x, y;
    vector<pair<int, int>> points;
    for (int i = 0; i < n; ++i) {
        int x1, y1; cin >> x1 >> y1;
        ++x[x1], ++y[y1];
        points.emplace_back(x1, y1);
    }
    ll ans = 0;
    for (auto p : points) {
        ans += (x[p.first]-1) * (y[p.second]-1);
    }
    cout << ans;

}

signed main()
{
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
//    ll t; cin >> t; while(t--)
    solve();
}

• Subtask 1: 100 / 100