#include <bits/stdc++.h>
using namespace std;
int main(){
ios_base::sync_with_stdio(false);
cin.tie(NULL);
#ifdef Local
freopen("in.txt","r",stdin);
freopen("out.txt","w",stdout);
#endif
int n;
cin >> n;
long long ans = 0;
map<int,int> cnt;
vector<pair<int,int>> v;
for(int i=1;i<=n;i++){
int x,y;
cin >> x >> y;
cnt[y]++;
v.push_back({y,x});
}
map<int,int> mp;
for(auto u:v){
mp[u.second] += cnt[u.first] - 1;
}
sort(v.begin(),v.end());
reverse(v.begin(),v.end());
map<int,int> mp2;
for(auto u:v){
mp[u.second] -= cnt[u.first] - 1;
ans += mp[u.second] + mp2[u.second];
mp2[u.second] += cnt[u.first] - 1;
}
cout << ans;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 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 |
0 ms |
204 KB |
Output is correct |
5 |
Correct |
0 ms |
204 KB |
Output is correct |
6 |
Correct |
1 ms |
204 KB |
Output is correct |
7 |
Correct |
1 ms |
332 KB |
Output is correct |
8 |
Correct |
1 ms |
332 KB |
Output is correct |
9 |
Correct |
1 ms |
332 KB |
Output is correct |
10 |
Correct |
1 ms |
332 KB |
Output is correct |
11 |
Correct |
1 ms |
332 KB |
Output is correct |
12 |
Correct |
9 ms |
972 KB |
Output is correct |
13 |
Correct |
9 ms |
1212 KB |
Output is correct |
14 |
Correct |
16 ms |
1804 KB |
Output is correct |
15 |
Correct |
190 ms |
7528 KB |
Output is correct |
16 |
Correct |
228 ms |
7932 KB |
Output is correct |
17 |
Correct |
180 ms |
7560 KB |
Output is correct |
18 |
Correct |
193 ms |
7664 KB |
Output is correct |
19 |
Correct |
467 ms |
13052 KB |
Output is correct |
20 |
Correct |
355 ms |
10796 KB |
Output is correct |
21 |
Correct |
502 ms |
13668 KB |
Output is correct |
22 |
Correct |
544 ms |
13732 KB |
Output is correct |