Submission #88606

#	Time	Username	Problem	Language	Result	Execution time	Memory
88606		Badral	Star triangles (IZhO11_triangle)	C++17	100 / 100	852 ms	13048 KiB

triangle

#include<bits/stdc++.h>

#define maxn 300000
#define ll long long
using namespace std;

pair<ll,ll> a[maxn+5];
map<ll, ll> u;
map<ll, ll> o;

int main() {
	ll n;
	cin >>n;
	for(ll i = 1; i <= n; i++) {
		cin >>a[i].first >>a[i].second;
		u[a[i].first]++;
		o[a[i].second]++;
	}
	ll s = 0;
	for(ll i = 1; i <= n; i++) {
		s += (u[a[i].first]-1) * (o[a[i].second]-1);
	}
	cout<<s;
}

• Subtask 1: 100 / 100