Submission #887307

#	Time	Username	Problem	Language	Result	Execution time	Memory
887307		alex_2008	Star triangles (IZhO11_triangle)	C++14	100 / 100	374 ms	12120 KiB

triangle

#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <cmath>
#include <iomanip>
#include <algorithm>
#include <vector>
#include <set>
#include <map>
#include <unordered_map>
#include <unordered_set>
#include <fstream>
#include <bitset>
typedef long long ll;
using namespace std;
const int N = 3e5 + 10;
int x[N], y[N];
int main() {
	int n;
	cin >> n;
	map <int, int> mpx, mpy;
	for (int i = 1; i <= n; i++) {
		cin >> x[i] >> y[i];
		mpx[x[i]]++;
		mpy[y[i]]++;
	}
	ll ans = 0;
	for (int i = 1; i <= n; i++) {
		ans += (mpx[x[i]] - 1) * 1ll * (mpy[y[i]] - 1);
	}
	cout << ans << "\n";
}

• Subtask 1: 100 / 100