Submission #382321

#	Time	Username	Problem	Language	Result	Execution time	Memory
382321		knightron0	Star triangles (IZhO11_triangle)	C++14	100 / 100	552 ms	12728 KiB

triangle

#include <bits/stdc++.h>
using namespace std;

#define pb push_back
#define fr first
#define sc second
#define clr(a, x) memset(a, x, sizeof(a))
#define dbg(x) cout<<"("<<#x<<"): "<<x<<endl;
#define printvector(arr) for (auto it = arr.begin(); it != arr.end(); ++it) cout<<*it<<" "; cout<<endl;
#define all(v) v.begin(), v.end()
#define lcm(a, b) (a * b)/__gcd(a, b)
#define int long long int
#define printvecpairs(vec) for(auto it: vec) cout<<it.fr<<' '<<it.sc<<endl;
#define endl '\n'
#define float long double

const int MOD = 1e9 + 7;
const int INF = 2e15;
const int MAXN = 1e5 + 5;

map<int, int> cntx, cnty;

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    #ifdef LOCAL
    freopen("input.txt", "r", stdin);
    #endif
    int n;
    cin>>n;
	vector<pair<int, int>> v;
	for(int i = 0;i<n;i++){
		int t1, t2; cin>>t1>>t2;
		v.pb({t1, t2});
		cntx[t1]++;
		cnty[t2]++;
	}
	int ans = 0;
	for(auto it: v){
		ans += (cntx[it.fr]-1) * (cnty[it.sc]-1);
	}
	cout<<ans<<endl;
    return 0;
}

• Subtask 1: 100 / 100