This submission is migrated from previous version of oj.uz, which used different machine for grading. This submission may have different result if resubmitted.
#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<ll,ll>
#define vi vector<int>
#define pb emplace_back
#define fi first
#define se second
#define all(n) (n).begin(),(n).end()
#define mem(n,m) memset(n,m,sizeof(n))
#define IOS ios::sync_with_stdio(0), cin.tie(0)
#define dbg(...) cerr<<#__VA_ARGS__<<" = ";_do(__VA_ARGS__);
template<typename A> void _do(A x){cerr<<x<<'\n';}
template<typename A,typename ...B> void _do(A x,B ...y){cerr<<x<<", ";_do(y...);}
const int mxn = 100005;
ll C(ll x){
return (x)*(x-1)*(x-2)/6*2;
}
ll P(ll x){
return C(x)*3;
}
ll n,m;
vi E[mxn], E2[mxn];
ll siz[mxn], ans=0, l[mxn], d[mxn], bcc[mxn], bcc_siz[mxn], dfn, bccid, vis[mxn], rt[mxn];
stack<int> s;
void dfs(int x,int p){
l[x] = d[x] = ++dfn;
s.push(x);
for(auto i:E[x]){
if(i==p) continue;
if(!d[i]){
dfs(i,x);
l[x] = min(l[x],l[i]);
}
else{
l[x] = min(l[x],d[i]);
}
}
if(l[x] == d[x]){
bccid++;
for(int i;i!=x;){
i = s.top(); s.pop();
bcc[i] = bccid;
}
}
}
void bcc_dfs(int x,int p,int anc){
rt[x] = anc;
siz[x] = bcc_siz[x];
vis[x] = 1;
for(auto i:E2[x]){
if(i==p) continue;
bcc_dfs(i,x,anc);
siz[x] += siz[i];
}
}
void bcc_dfs2(int x,int p,int anc){
vis[x] = 1;
for(auto i:E2[x]){
if(i==p) continue;
bcc_dfs2(i,x,anc);
ans += siz[i] * (siz[anc] - siz[i] - bcc_siz[x]) * bcc_siz[x];
}
ans += (siz[x]-bcc_siz[x]) * (siz[anc]-siz[x]);
}
signed main(){
IOS;
cin>>n>>m;
for(int i=1,a,b;i<=m;i++){
cin>>a>>b;
E[a].pb(b);
E[b].pb(a);
}
for(int i=1;i<=n;i++) if(!d[i]) dfs(i,0);
for(int i=1;i<=n;i++){
//dbg(i, bcc[i]);
bcc_siz[bcc[i]]++;
for(auto j:E[i]){
if(bcc[i] == bcc[j]) continue;
E2[bcc[i]].pb(bcc[j]);
E2[bcc[j]].pb(bcc[i]);
}
}
for(int i=1;i<=bccid;i++){
sort(all(E2[i]));
E2[i].resize(unique(all(E2[i]))-E2[i].begin());
}
for(int i=1;i<=bccid;i++){
if(!vis[i]){
bcc_dfs(i,0,i);
}
}
// for(int i=1;i<=bccid;i++){
// dbg(i, siz[i]);
// }
mem(vis,0);
for(int i=1;i<=bccid;i++){
if(bcc_siz[i]>=3){
ll x = bcc_siz[i];
ans += P(x);
ans += (x-1) * (x-1) * (siz[rt[i]] - x) * 2;
}
if(!vis[i]){
bcc_dfs2(i,0,i);
}
}
cout<<ans<<'\n';
}
/*
3 3
1 2
2 3
3 1
4 4
1 2
2 3
3 4
2 4
5 4
1 2
2 3
1 3
4 5
*/
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