Submission #170291

#	Time	Username	Problem	Language	Result	Execution time	Memory
170291		div2der	Star triangles (IZhO11_triangle)	C++14	0 / 100	2 ms	380 KiB

triangle

#include <iostream>
#include <set>
#include <map>
#include <algorithm>
using namespace std;

#define sz(s) (int)(s.size())
#define eb emplace_back
#define all(x) x.begin(), x.end()

const int N = 2e6;
const int NN = 4e3;

#define ll long long

ll x[N], y[N], cntx[N], cnty[N];

void solve() {
	int n;
	cin >> n;
	for (int i = 1; i <= n; ++ i) {
		cin >> x[i] >> y[i];
		++cntx[x[i]];
		++cnty[y[i]];
	}
	ll res = 0;
	for (int i = 1; i <= n; ++ i)
		res += ((cntx[x[i]] - 1) * (cnty[y[i]] - 1));
	cout << res;
}

int main () {	
	solve();
	return 0;
}

• Subtask 1: 0 / 100