#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int MN = 2e5+5;
int N,M,s,e,D[MN],cur,par[MN];
ll sz[MN],ans;
vector<int> G[MN];
bool ch[MN];
int fnd(int s)
{
return par[s]==s ? s : par[s]=fnd(par[s]);
}
void join(int x, int y)
{
x = fnd(x), y = fnd(y);
if(x==y) return;
par[y] = x;
sz[x] += sz[y];
}
void act(int s)
{
ch[s] = 1;
int p = 0;
for(int e : G[s]){
if(p) join(e,p);
p = e;
}
for(int e : G[s]) if(!ch[e]) act(e);
}
int main()
{
cin >> N >> M;
for(int i=1; i<=N; i++) par[i] = i, sz[i] = 1;
for(int i=0; i<M; i++){
cin >> s >> e;
G[s].push_back(e);
D[s]++;
if(D[s]>D[cur]) cur = s;
}
for(int i=1; i<=N; i++) if(!ch[i]) act(i);
for(int i=1; i<=N; i++){
if(fnd(i)==i) ans += sz[i]*(sz[i]-1);
for(int e : G[i]) if(fnd(i)!=fnd(e)) ans++;
}
cout << ans;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
6 ms |
5240 KB |
Output is correct |
2 |
Correct |
6 ms |
5112 KB |
Output is correct |
3 |
Correct |
6 ms |
5068 KB |
Output is correct |
4 |
Incorrect |
7 ms |
5112 KB |
Output isn't correct |
5 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Incorrect |
12 ms |
5496 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
175 ms |
8152 KB |
Output is correct |
2 |
Incorrect |
290 ms |
12636 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |