Submission #976878

#	Time	Username	Problem	Language	Result	Execution time	Memory
976878		vjudge1	Star triangles (IZhO11_triangle)	C++17	100 / 100	406 ms	15464 KiB

triangle

#include<bits/stdc++.h>
using namespace std;
#define int long long

signed main(){
    int n;
    cin >> n;

    map<int, int> cx, cy;
    int x[n+1], y[n+1];
    for(int i = 0; i < n; i++){
        cin >> x[i] >> y[i];

        cx[x[i]]++;
        cy[y[i]]++;
    }

    int ans = 0;
    for(int i = 0; i < n; i++){
        ans += (cx[x[i]] - 1) * (cy[y[i]] - 1);
    }

    cout << ans << endl;
}

• Subtask 1: 100 / 100