Submission #337565

#	Time	Username	Problem	Language	Result	Execution time	Memory
337565		amunduzbaev	Star triangles (IZhO11_triangle)	C++14	0 / 100	1 ms	364 KiB

triangle

/** made by amunduzbaev **/
#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ub upper_bound
#define lb lower_bound
#define ll long long 
#define ld long double 
#define pii pair<int, int>
#define pll pair<ll, ll>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(),x.rend()
#define fastios ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define vll vector<ll>
#define vii vector<int>
const int N = 1e5+5;
const int mod = 1e9+7;
const ll inf = 1e18;
const ld Pi = acos(-1);
ll n, m, k, ans;

void solve(){
	fastios
	cin>>n;
	map<ll, ll> x, y;
	map<ll, vll> xx, yy;
	for(int i=0;i<n;i++){
		ll a, b;
		cin>>a>>b;
		y[b]++;
		x[a]++;
		xx[a].pb(b);
	}
	
	for(auto tmp : x){
		ll cur = tmp.ff, cnt = 0, bb = 0;
		for(auto ttmp : xx[cur]){
			ans += (cnt * bb);
			cnt++, bb += y[ttmp]-1;
		}
		cur = tmp.ff, cnt = 0, bb = 0;
		for(auto ttmp = xx[cur].rbegin(); ttmp != xx[cur].rend(); ttmp++){
			ans += (cnt * bb);
			cnt++, bb += y[*ttmp]-1;
		}
		
	}
	
	cout<<ans<<"\n";
	return;
}

/*

10
0 0
3 3
0 3
3 0
-3 0
0 -3
-3 -3
3 -3
-3 3
6 0

8
2 3
4 5
5 6
8 3
5 3
2 6
5 5
4 6

12
0 0
0 1
0 2
0 3
1 0
2 0
3 0
3 1
3 2
3 3
1 3
2 3

*/

int main(){
	fastios
	
	int t = 1;
	if(t) solve();
	else {
		cin>>t;
		while (t--) solve();
	}
	return 0;
}

• Subtask 1: 0 / 100