#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define ll long long
#define ull unsigned long long
#define ld long double
#define chad char
#define mod 1'000'000'007
#define dim 100005
#define lim 1000000
#define BASE 31
#define NMAX 21'005
#define FOR(i,a,b) for(int i=(a); i<=(b); i++)
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define pii pair<int,int>
#define pb push_back
#define mp make_pair
#define nr_biti __builtin_popcount
using namespace __gnu_pbds;
using namespace std;
ifstream fin("b.in");
ofstream fout("b.out");
int t=1;
ll n,m;
vector<int> g[dim];
vector<int> gt[dim];
int low[dim],tin[dim];
bool viz[dim];
int timer;
unordered_map<int,bool> is_bridge[dim];
ll wrong_ones[dim];
void dfs(int nod,int daddy=0)
{
viz[nod]=1;
low[nod]=tin[nod]=++timer;
for(auto it:g[nod])
{
if(it==daddy)
continue;
if(viz[it])
{
low[nod]=min(low[nod],tin[it]);
}
else
{
dfs(it,nod);
low[nod]=min(low[nod],low[it]);
if(low[it]>tin[nod])
is_bridge[nod][it]=is_bridge[it][nod]=1;
}
}
}
int comp[dim],nr;
ll sz_comp[dim];
void dfs1(int nod)
{
viz[nod]=1;
comp[nod]=nr;
sz_comp[nr]++;
for(auto it:g[nod])
{
if(!viz[it] && !is_bridge[nod][it])
dfs1(it);
}
}
ll ans;
ll sz[dim];
void dfs2(int nod,int daddy=0)
{
viz[nod]=1;
sz[nod]+=sz_comp[nod];
for(auto it:gt[nod])
{
if(it==daddy)
continue;
dfs2(it,nod);
sz[nod]+=sz[it];
}
// nu pot sa iau un nod marginal ca start
if(sz_comp[nod]>=3)
{
// pot sa aleg toate in aceiasi componenta
ans+=(sz_comp[nod]*(sz_comp[nod]-1)*(sz_comp[nod]-2)-wrong_ones[nod]);
// acum pot sa aleg 2 din aceiasi componenta
// sa zicem ca vreau sa merg in sus intai
// e clar ca nu pot sa iau nodul de legatura ca start (as trece de 2 ori prin el)
ll add=(sz_comp[nod]-1)*(sz_comp[nod]-1);
ans+=(2*(n-sz[nod])*add);
// daca merg in jos
// sa zicem ca am mai multi fii f1,f2,f3,...fk
// in cazul in care imi aleg un capat in unul din acesti fii e imposibil ca celalalt capat sa fie in nodul de
// legatura
// sa zicem ca am avea sum (sz_comp[nod]-1)*(sz_comp[nod]-1)*sz[f1] + ...
// (sz_comp[nod]-1)*(sz_comp[nod]-1)*(sz[nod]-sz_comp[nod])
ans+=(2*(sz[nod]-sz_comp[nod])*add);
// acum sa zicem ca aleg un singur nod din componenta mea
// pot sa iau unul de sus si unul de jos
// adk (sz[nod]-sz_comp[nod])*(n-sz[nod])*sz_comp[nod]
// pot sa iau 2 noduri din subarbori diferiti ai fiilor
// sz[f1]*(sz[nod]-sz_comp[nod]-sz[f1]) + ...
ans+=(2*(n-sz[nod])*(sz_comp[nod])*(sz[nod]-sz_comp[nod]));
for(auto it:gt[nod])
{
if(it==daddy)
continue;
ans+=(sz[it]*(sz[nod]-sz_comp[nod]-sz[it])*sz_comp[nod]);
}
}
else if(sz_comp[nod]==2)
{
ll add=(sz_comp[nod]-1)*(sz_comp[nod]-1);
ans+=(2LL*(n-sz[nod])*add);
ans+=(2LL*(sz[nod]-sz_comp[nod])*add);
ans+=(2LL*(n-sz[nod])*(sz_comp[nod])*(sz[nod]-sz_comp[nod]));
for(auto it:gt[nod])
{
if(it==daddy)
continue;
ans+=(sz[it]*(sz[nod]-sz_comp[nod]-sz[it])*sz_comp[nod]);
}
}
else if(sz_comp[nod]==1)
{
ans+=(2LL*(n-sz[nod])*(sz_comp[nod])*(sz[nod]-sz_comp[nod]));
for(auto it:gt[nod])
{
if(it==daddy)
continue;
ans+=(sz[it]*(sz[nod]-sz_comp[nod]-sz[it])*sz_comp[nod]);
}
}
}
ll rep;
void dfs_aux(int nod,int daddy=0)
{
rep+=sz_comp[nod];
for(auto it:gt[nod])
{
if(it==daddy)
continue;
dfs_aux(it,nod);
}
}
int rep_grupa[dim];
set<int> s;
stack<pii> d;
void pop_until(int u,int v,int c)
{
s.clear();
while(d.top().first!=u || d.top().second!=v)
{
s.insert(d.top().first);
s.insert(d.top().second);
d.pop();
}
s.insert(u);
s.insert(v);
d.pop();
ll N=(ll)s.size();
wrong_ones[c]+=((N)*(N-1)*(sz_comp[c]-N));
}
void dfs_componente(int nod,int daddy,int c)
{
viz[nod]=1;
tin[nod]=low[nod]=++timer;
for(auto it:g[nod])
{
if(it==daddy || comp[it]!=c)
continue;
if(viz[it])
{
low[nod]=min(low[nod],tin[it]);
}
else
{
d.push(mp(nod,it));
dfs_componente(it,nod,c);
low[nod]=min(low[nod],low[it]);
if(low[it]>=tin[nod])
pop_until(nod,it,c);
}
}
}
void solve()
{
cin >> n >> m;
for(int i=1; i<=m; i++)
{
int x,y;
cin >> x >> y;
g[x].pb(y);
g[y].pb(x);
}
for(int i=1; i<=n; i++)
{
if(!viz[i])
dfs(i);
}
for(int i=1; i<=n; i++)
viz[i]=0;
for(int i=1; i<=n; i++)
{
if(!viz[i])
{
++nr;
rep_grupa[nr]=i;
dfs1(i);
}
}
for(int i=1; i<=n; i++)
{
for(auto it:g[i])
if(comp[i]!=comp[it])
gt[comp[i]].pb(comp[it]);
}
for(int i=1; i<=n; i++)
viz[i]=0;
for(int i=1; i<=nr; i++)
{
timer=0;
dfs_componente(rep_grupa[i],0,i);
}
for(int i=1; i<=n; i++)
viz[i]=0;
for(int i=1; i<=nr; i++)
{
if(!viz[i])
{
rep=0;
dfs_aux(i);
n=rep;
dfs2(i);
}
}
cout << ans;
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
cout.tie(nullptr);
//cin >> t;
while(t--)
solve();
return 0;
}
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
9 ms |
10576 KB |
Output is correct |
2 |
Correct |
9 ms |
10576 KB |
Output is correct |
3 |
Correct |
9 ms |
10576 KB |
Output is correct |
4 |
Correct |
9 ms |
10576 KB |
Output is correct |
5 |
Correct |
9 ms |
10576 KB |
Output is correct |
6 |
Correct |
7 ms |
10576 KB |
Output is correct |
7 |
Incorrect |
8 ms |
10524 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
9 ms |
10576 KB |
Output is correct |
2 |
Correct |
9 ms |
10576 KB |
Output is correct |
3 |
Correct |
9 ms |
10576 KB |
Output is correct |
4 |
Correct |
9 ms |
10576 KB |
Output is correct |
5 |
Correct |
9 ms |
10576 KB |
Output is correct |
6 |
Correct |
7 ms |
10576 KB |
Output is correct |
7 |
Incorrect |
8 ms |
10524 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
162 ms |
45896 KB |
Output is correct |
2 |
Correct |
150 ms |
45896 KB |
Output is correct |
3 |
Correct |
171 ms |
42268 KB |
Output is correct |
4 |
Correct |
174 ms |
44104 KB |
Output is correct |
5 |
Correct |
144 ms |
38524 KB |
Output is correct |
6 |
Correct |
143 ms |
40204 KB |
Output is correct |
7 |
Correct |
156 ms |
38472 KB |
Output is correct |
8 |
Correct |
155 ms |
39752 KB |
Output is correct |
9 |
Correct |
145 ms |
36936 KB |
Output is correct |
10 |
Correct |
157 ms |
37448 KB |
Output is correct |
11 |
Correct |
101 ms |
32588 KB |
Output is correct |
12 |
Correct |
114 ms |
32328 KB |
Output is correct |
13 |
Correct |
100 ms |
32000 KB |
Output is correct |
14 |
Correct |
99 ms |
31556 KB |
Output is correct |
15 |
Correct |
76 ms |
29976 KB |
Output is correct |
16 |
Correct |
113 ms |
29140 KB |
Output is correct |
17 |
Correct |
13 ms |
13916 KB |
Output is correct |
18 |
Correct |
13 ms |
13904 KB |
Output is correct |
19 |
Correct |
14 ms |
13904 KB |
Output is correct |
20 |
Correct |
13 ms |
13960 KB |
Output is correct |
21 |
Correct |
13 ms |
13828 KB |
Output is correct |
22 |
Correct |
13 ms |
13904 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
8 ms |
10832 KB |
Output is correct |
2 |
Correct |
11 ms |
10832 KB |
Output is correct |
3 |
Correct |
9 ms |
10832 KB |
Output is correct |
4 |
Correct |
9 ms |
10832 KB |
Output is correct |
5 |
Correct |
8 ms |
10832 KB |
Output is correct |
6 |
Correct |
12 ms |
10836 KB |
Output is correct |
7 |
Correct |
9 ms |
10832 KB |
Output is correct |
8 |
Correct |
8 ms |
10832 KB |
Output is correct |
9 |
Correct |
8 ms |
10936 KB |
Output is correct |
10 |
Correct |
10 ms |
10832 KB |
Output is correct |
11 |
Correct |
10 ms |
10832 KB |
Output is correct |
12 |
Correct |
10 ms |
10832 KB |
Output is correct |
13 |
Correct |
12 ms |
10832 KB |
Output is correct |
14 |
Correct |
9 ms |
10832 KB |
Output is correct |
15 |
Correct |
12 ms |
10832 KB |
Output is correct |
16 |
Correct |
8 ms |
10832 KB |
Output is correct |
17 |
Correct |
10 ms |
10972 KB |
Output is correct |
18 |
Correct |
12 ms |
10832 KB |
Output is correct |
19 |
Correct |
10 ms |
10832 KB |
Output is correct |
20 |
Correct |
10 ms |
10832 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
184 ms |
38728 KB |
Output is correct |
2 |
Correct |
149 ms |
38824 KB |
Output is correct |
3 |
Correct |
166 ms |
38728 KB |
Output is correct |
4 |
Correct |
154 ms |
38728 KB |
Output is correct |
5 |
Correct |
130 ms |
38728 KB |
Output is correct |
6 |
Correct |
157 ms |
43592 KB |
Output is correct |
7 |
Correct |
132 ms |
41976 KB |
Output is correct |
8 |
Correct |
165 ms |
41044 KB |
Output is correct |
9 |
Correct |
169 ms |
40264 KB |
Output is correct |
10 |
Correct |
142 ms |
38728 KB |
Output is correct |
11 |
Correct |
162 ms |
38728 KB |
Output is correct |
12 |
Correct |
164 ms |
38600 KB |
Output is correct |
13 |
Correct |
142 ms |
38792 KB |
Output is correct |
14 |
Correct |
154 ms |
37704 KB |
Output is correct |
15 |
Correct |
123 ms |
36424 KB |
Output is correct |
16 |
Correct |
90 ms |
30536 KB |
Output is correct |
17 |
Correct |
147 ms |
40516 KB |
Output is correct |
18 |
Correct |
146 ms |
40520 KB |
Output is correct |
19 |
Correct |
141 ms |
40332 KB |
Output is correct |
20 |
Correct |
139 ms |
40076 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
9 ms |
10832 KB |
Output is correct |
2 |
Correct |
10 ms |
10832 KB |
Output is correct |
3 |
Incorrect |
8 ms |
10832 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
149 ms |
38576 KB |
Output is correct |
2 |
Correct |
165 ms |
38596 KB |
Output is correct |
3 |
Incorrect |
191 ms |
35672 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
9 ms |
10576 KB |
Output is correct |
2 |
Correct |
9 ms |
10576 KB |
Output is correct |
3 |
Correct |
9 ms |
10576 KB |
Output is correct |
4 |
Correct |
9 ms |
10576 KB |
Output is correct |
5 |
Correct |
9 ms |
10576 KB |
Output is correct |
6 |
Correct |
7 ms |
10576 KB |
Output is correct |
7 |
Incorrect |
8 ms |
10524 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
9 ms |
10576 KB |
Output is correct |
2 |
Correct |
9 ms |
10576 KB |
Output is correct |
3 |
Correct |
9 ms |
10576 KB |
Output is correct |
4 |
Correct |
9 ms |
10576 KB |
Output is correct |
5 |
Correct |
9 ms |
10576 KB |
Output is correct |
6 |
Correct |
7 ms |
10576 KB |
Output is correct |
7 |
Incorrect |
8 ms |
10524 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |