Submission #1343858

#	Time	Username	Problem	Language	Result	Execution time	Memory
1343858		nicolo_010	Star triangles (IZhO11_triangle)	C++20	100 / 100	775 ms	24624 KiB

triangle

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using pii = pair<int, int>;

int main() {
	ios::sync_with_stdio(0);
	cin.tie(0);
	int n; cin >> n;
	map<int, int> rows, col;
	map<pii, int> mp;
	vector<pii> a(n);
	for (int i=0; i<n; i++) {
		cin >> a[i].first >> a[i].second;
		auto [x, y] = a[i];
		mp[a[i]]++;
		rows[x]++;
		col[y]++;
	}	
	ll ans=0;
	for (int i=0; i<n; i++) {
		auto [x, y] = a[i];
		int r = rows[x];
		int c = col[y];
		ans += (r-1)*(c-1);
	}
	cout << ans << "\n";
}

• Subtask 1: 100 / 100