Submission #531534

#	Time	Username	Problem	Language	Result	Execution time	Memory
531534		christinelynn	Star triangles (IZhO11_triangle)	C++17	100 / 100	400 ms	10208 KiB

triangle

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

signed main(){
  cin.tie(0) -> ios_base::sync_with_stdio(0);

  int n;
  cin >> n;
  vector<int> x(n), y(n);
  map<int,int> px, py;
  for(int i=0;i<n;i++)
  {
    cin >> x[i] >> y[i];
    px[x[i]]++;
    py[y[i]]++;
  }
  int ans = 0;
  for(int i=0;i<n;i++)
  {
    int cx = 0, cy = 0;
    if(px.count(x[i])) cx = px[x[i]];
    if(py.count(y[i])) cy = py[y[i]];
    ans += (cx - 1) * (cy - 1);
  }
  cout << ans << '\n';
  
}

• Subtask 1: 100 / 100