#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...) 42
#endif
int main() {
ios::sync_with_stdio(false); cin.tie(nullptr);
int n; cin >> n;
vector<int> x(n), y(n);
map<int, int> a, b;
for (int i = 0; i < n; ++i) {
cin >> x[i] >> y[i];
++a[x[i]], ++b[y[i]];
}
int res = 0;
for (int i = 0; i < n; ++i) {
res += a[x[i] - 1] * b[y[i] - 1];
}
cout << res;
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
0 ms |
600 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |