#include <bits/stdc++.h>
#define pb push_back
#define fi first
#define se second
typedef long long ll;
using namespace std;
ll n, ans;
pair<ll,ll>arr[300005];
ll total[300005];
int main(){
cin >> n;
for(int i = 0; i < n; i++){
cin >> arr[i].fi >> arr[i].se;
total[arr[i].se]++;
}
for(int i = 0; i < n; i++){
for(int j = 0; j < n; j++){
if(i==j || arr[i].fi != arr[j].fi)continue;
ans += total[arr[j].se]-1;
// cout << total[arr[j].se] << endl;
// cout << arr[i].fi << " " << arr[i].se << " : " << arr[j].fi << " " << arr[j].se << " : " << ans << endl;
}
}
cout << ans << endl;
}
//tle lmao
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
0 ms |
204 KB |
Output is correct |
2 |
Correct |
1 ms |
204 KB |
Output is correct |
3 |
Correct |
1 ms |
204 KB |
Output is correct |
4 |
Correct |
1 ms |
296 KB |
Output is correct |
5 |
Incorrect |
1 ms |
204 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |