Submission #41333

#	Time	Username	Problem	Language	Result	Execution time	Memory
41333		IvanC	Star triangles (IZhO11_triangle)	C++14	100 / 100	521 ms	42360 KiB

triangle

#include <bits/stdc++.h>
using namespace std;
const int MAXN = 3*1e5 + 10;
typedef long long ll;
ll N,ans,c1[MAXN],c2[MAXN];
map<ll,ll> X,Y;
int main(){
	cin.tie(0);ios_base::sync_with_stdio(0);
	cin >> N;
	for(int i = 1;i<=N;i++){
		cin >> c1[i] >> c2[i];
		X[c1[i]]++;
		Y[c2[i]]++;
	}
	for(int i = 1;i<=N;i++){
		ans += (X[c1[i]] - 1)*(Y[c2[i]] - 1);
	}
	cout << ans << endl;
	return 0;
}

• Subtask 1: 100 / 100