Submission #166757

#	Time	Username	Problem	Language	Result	Execution time	Memory
166757		Lightning	Star triangles (IZhO11_triangle)	C++14	100 / 100	561 ms	9248 KiB

triangle

#include <iostream>
#include <algorithm>
#include <vector>
#include <cmath>
#include <set>
#include <map>
#include <iomanip>
#include <stack>
#include <queue>
#include <deque>
 
using namespace std;
 
typedef long long ll;
typedef pair <int, int> pii;
 
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define pb push_back
#define ppb pop_back
#define mkp make_pair
#define F first
#define S second
#define show(a) cerr << #a <<" -> "<< a <<"\n"
#define fo(a, b, c, d) for(int (a) = (b); (a) <= (c); (a) += (d))
#define foo(a, b, c ,d) for(int (a) = (b); (a) >= (c); (a) -= (d))
//#define int ll
 
const int N = 4e5;
const int INF = 1e9;
 
int n, x[N], y[N];
ll ans;
map <int, int> cntX, cntY;
 
int main () {
	ios_base::sync_with_stdio(false);
	cin >> n;
	fo(i, 1, n, 1) {
		cin >> x[i] >> y[i];
		++cntX[x[i]];
		++cntY[y[i]];
	}	
	fo(i, 1, n, 1) {
		ans += 1ll * (cntX[x[i]] - 1) * (cntY[y[i]] - 1);	
	}
	cout << ans;
	return 0;
}

• Subtask 1: 100 / 100