Submission #716572

#	Time	Username	Problem	Language	Result	Execution time	Memory
716572		ngano_upat_na	Star triangles (IZhO11_triangle)	C++17	100 / 100	1287 ms	30804 KiB

triangle

#include "bits/stdc++.h"
using namespace std;
using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    
    int n;
    cin >> n;
    multiset<int> mx, my;
    vector<pair<int,int>> v(n);
    for (auto &e:v) {
        cin >> e.first >> e.second;
        mx.insert(e.first);
        my.insert(e.second);
    }   
    
    ll ans = 0;
    for (int i=0; i<n; i++) {
        int x = v[i].first, y = v[i].second;
        ll cx = mx.count(x) - 1;
        ll cy = my.count(y) - 1;
        ans = ans + (cx * cy);
    }   
    cout << ans;
}   

• Subtask 1: 100 / 100