Submission #1116448

#	Time	Username	Problem	Language	Result	Execution time	Memory
1116448		heey	Star triangles (IZhO11_triangle)	C++14	100 / 100	408 ms	29768 KiB

triangle

#include<bits/stdc++.h>
using namespace std;
#define int long long
signed main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    map<pair<int,int>, int> p;
    map<int,int> x;
    map<int,int> y;
    int n; cin >> n;
    for(int i = 0; i < n; i++){
        int X, Y; cin >> X >> Y;
        p[{X,Y}]++;
        x[X]++;
        y[Y]++;
    }
    int res = 0;
    for(pair<pair<int,int>, int> a : p){
        res += a.second * (x[a.first.first] - a.second) * (y[a.first.second] - a.second);
    }
    cout << res << '\n';
}

• Subtask 1: 100 / 100