Submission #645537

#	Time	Username	Problem	Language	Result	Execution time	Memory
645537		phoenix	Star triangles (IZhO11_triangle)	C++17	100 / 100	276 ms	13500 KiB

triangle

#include<bits/stdc++.h>

using namespace std;

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0), cout.tie(0);

    int n;
    cin >> n;
    vector<pair<int, int>> v;
    map<int, int> cntX, cntY;
    for(int i = 1;i <= n;i++) {
        int x, y;
        cin >> x >> y;
        cntX[ x ]++;
        cntY[ y ]++;
        v.push_back({x, y});
    }
    long long res = 0;
    for(auto c : v) {
        res += 1ll * (cntX[ c.first ] - 1) * (cntY[ c.second ] - 1);
    }
    cout << res;
}

• Subtask 1: 100 / 100