#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,sse4.1,sse4.2,popcnt,abm,mmx,avx,avx2,fma")
#include <bits/stdc++.h>
using namespace std;
#ifdef LOCAL
#include "debug.h"
#else
#define debug(...)
#endif
using ll=long long;
using pii=array<int,2>;
const int N=200005;
int n,m,u[N],v[N];
ll ans,sz,dp[N];
int V[N], bn, dn, T[N];
vector<pii> G[N];
vector<int> BCC[N], L[N], S;
int GetBCC(int cur, int prev = 0) {
sz++;
int ret = V[cur] = ++dn;
for (auto& [next, edge] : G[cur]) {
if (next == prev) continue;
if (V[cur] > V[next]) S.push_back(edge);
if (V[next]) ret = min(ret, V[next]);
else {
int temp = GetBCC(next, cur);
ret = min(ret, temp);
if (temp < V[cur]) continue;
bn++;
while (1) {
int t = S.back();
if(T[u[t]] != bn){
T[u[t]] = bn;
BCC[bn].push_back(u[t]);
L[u[t]].push_back(bn);
}
if(T[v[t]] != bn){
T[v[t]] = bn;
BCC[bn].push_back(v[t]);
L[v[t]].push_back(bn);
}
S.pop_back();
if (t == edge) break;
}
debug(BCC[bn]);
}
}
return ret;
}
void dfsBCC(int b,int p){
dp[b]=BCC[b].size();
for(int u: BCC[b]) if(p!=u){
ll S=0;
for(int b2: L[u]){
if(!dp[b2]){
dfsBCC(b2,u);
ans-=(ll)(BCC[b2].size()-1)*(sz+1-dp[b2])*(sz-dp[b2]);
S+=dp[b2]-1;
dp[b]+=dp[b2]-1;
}
}
ans-=(BCC[b].size()-1)*(S+1)*S;
}
}
int main(){
ios::sync_with_stdio(false); cin.tie(0);
cin>>n>>m;
for(int i=1;i<=m;i++){
cin>>u[i]>>v[i];
G[u[i]].push_back({v[i],i});
G[v[i]].push_back({v[i],i});
}
for(int u=1;u<=n;u++) if(!V[u]){
sz=0;
GetBCC(u);
ans+=sz*(sz-1)*(sz-2);
dfsBCC(bn,0);
}
cout<<ans;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
5 ms |
16984 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
5 ms |
16984 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
44 ms |
23756 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
5 ms |
16988 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
51 ms |
24528 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
5 ms |
16988 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
48 ms |
24524 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
5 ms |
16984 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Incorrect |
5 ms |
16984 KB |
Output isn't correct |
2 |
Halted |
0 ms |
0 KB |
- |