Submission #881919

#	Time	Username	Problem	Language	Result	Execution time	Memory
881919		dosts	Star triangles (IZhO11_triangle)	C++17	100 / 100	254 ms	20412 KiB

triangle

#include <bits/stdc++.h>
using namespace std;
#define sp << " " << 
#define int long long
#define vi vector<int>
#define F(xxx,yyy) for (int xxx=1;xxx<=yyy;xxx++)
#define pii pair<int,int>
const int N = 5e5+1,inf = 1e18;

void solve() {
  int n;
  cin >> n;
  map<int,int> xc,yc;
  vector<pii> ps;
  F(i,n) {
    int a,b;
    cin >> a >> b;
    xc[a]++;
    yc[b]++;
    ps.push_back({a,b});
  }
  int ans = 0;
  for (auto it : ps) {
    ans+=(xc[it.first]-1)*(yc[it.second]-1);
  }
  cout << ans << endl;
}	
    
                  
                             
signed main() { 
  ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
  #ifdef Local
  freopen("in","r",stdin);
  freopen("out","w",stdout);
  #endif
  int t = 1;
  //cin >> t;
	F(i,t) solve();
}

• Subtask 1: 100 / 100