Submission #532118

#	Time	Username	Problem	Language	Result	Execution time	Memory
532118		gilbirb	Star triangles (IZhO11_triangle)	C++14	0 / 100	0 ms	332 KiB

triangle

#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
typedef long long ll;
using namespace std;

ll n, ans;
pair<ll,ll>arr[300005];
ll x[300005], y[300005];

int main(){
	cin >> n;
	for(int i = 0; i < n; i++){
		cin >> arr[i].fi >> arr[i].se;
		x[arr[i].fi]++; y[arr[i].se]++;
	}
	for(int i = 0; i < n; i++){
		ans += (x[arr[i].fi]-1) * (y[arr[i].se]-1);
	}
	cout << ans << endl;
}

• Subtask 1: 0 / 100