#include <bits/stdc++.h>
#define int long long
using namespace std;
const int mod = 1e9 + 7;
const int maxn = 1e5 + 10;
int n,m;
vector <int> adj[maxn];
stack <int> st;
int l[maxn],t[maxn],cnt,scc,id[maxn];
int dp[maxn],dp2[maxn],s[maxn];
vector <int> adj2[maxn];
int ans = 0LL;
bool dau[maxn];
void dfs(int x, int p)
{
st.push(x);
l[x] = t[x] = ++cnt;
for (int i:adj[x])
if (i!=p)
{
if (!t[i])
{
dfs(i,x);
l[x]=min(l[x],l[i]);
}
else l[x]=min(l[x],t[i]);
}
if (l[x]==t[x])
{
scc++; int temp;
do
{
temp = st.top(); st.pop();
s[scc]++;
id[temp] = scc;
}
while (temp!=x);
}
}
void dfs2(int x, int p)
{
dp[x] = 0;
for (int i:adj2[x])
if (i!=p)
{
dfs2(i,x);
// cout<<temp<<" : "<<dp[i]+s[i]<<' '<<s[x]<<endl;
dp[x] = (dp[x] + dp[i] + s[i]) ;
}
}
void dfs3(int x, int p, int val)
{
dp2[x] = val;
// cout<<val<<" : "<<temp<<" : "<<s[x]<<endl;
vector <int> pre,suf;
for (int i:adj2[x])
if (i!=p)
{
pre.push_back((dp[i]+s[i]) );
suf.push_back((dp[i]+s[i]) );
}
val = (val + s[x]) ;
// cout<<x<<" :: "<<val<<endl;
// for (int i:pre) cout<<i<<' '; cout<<"@@@@@@@@@@@"<<endl;
// for (int i:suf) cout<<i<<' '; cout<<"@@@@@@@@@@@"<<endl;
for (int i=1; i<pre.size(); i++) pre[i] = (pre[i-1] + pre[i]) ;
for (int i=suf.size()-2; i>=0; i--) suf[i] = (suf[i+1] + suf[i]) ;
// cout<<(int)suf.size()<<"@%$@%#$@"<<endl;
int cnt2=0;
for (int i:adj2[x])
if (i!=p)
{
int val2 = val;
// cerr<<val2<<' '<<cnt2<<" -> ";
if (cnt2>0) val2 = (val2 + pre[cnt2-1]) ;
if (cnt2<=(int)suf.size()-2) val2 = (val2 + suf[cnt2+1]) ;
// cerr<<val<<endl;
cnt2++;
dfs3(i,x,val2);
}
}
void dfs4(int x, int p, int sz)
{
int val = dp2[x];
int temp = (sz - s[x] - val);
if (temp>0&&val>0)
ans += s[x]*val*temp;
for (int i:adj2[x])
if (i!=p)
{
dfs4(i,x,sz);
val = dp[i]+s[i];
temp = sz - s[x] - val;
if (temp>0&&val>0) ans+=s[x]*val*temp;
}
}
signed main()
{
ios_base::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
// freopen("dualthon.inp","r",stdin);
// freopen("dualthon.ans","w",stdout);
cin>>n>>m;
for (int i=1; i<=m; i++)
{
int u,v; cin>>u>>v;
adj[u].push_back(v);
adj[v].push_back(u);
}
cnt = scc= 0;
vector <int> root;
for (int i=1; i<=n; i++) if (!t[i]) dfs(i,i), root.push_back(id[i]);
for (int i=1; i<=n; i++)
for (int j:adj[i])
if (id[i]!=id[j])
{
adj2[id[i]].push_back(id[j]);
}
for (int i=1; i<=scc; i++)
{
sort(adj2[i].begin(),adj2[i].end());
adj2[i].resize(unique(adj2[i].begin(),adj2[i].end())-adj2[i].begin());
}
for (int i:root) dfs2(i,i);
for (int i:root) dfs3(i,i,0);
for (int i=1; i<=scc; i++)
{
int sl = s[i];
// cout<<i<<" := "<<dp[i]<<' '<<dp2[i]<<endl;
int temp = 0;
if (sl>=3)
{
temp = sl*(sl-1)*(sl-2);
ans = (ans + temp);
}
if (sl>=2)
{
temp = (sl-1)*(sl-1);
// cout<<temp<<" "<<dp[i]<<' '<<dp2[i]<<endl;
ans += temp*dp[i]*2;
ans += temp*dp2[i]*2;
}
}
for (int i:root) dfs4(i,i,dp[i]+s[i]);
cout<<ans<<'\n';
}
Compilation message
count_triplets.cpp: In function 'void dfs3(long long int, long long int, long long int)':
count_triplets.cpp:68:20: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
68 | for (int i=1; i<pre.size(); i++) pre[i] = (pre[i-1] + pre[i]) ;
| ~^~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
4948 KB |
Output is correct |
2 |
Correct |
3 ms |
4948 KB |
Output is correct |
3 |
Correct |
4 ms |
4948 KB |
Output is correct |
4 |
Correct |
3 ms |
4948 KB |
Output is correct |
5 |
Correct |
3 ms |
4948 KB |
Output is correct |
6 |
Correct |
3 ms |
4948 KB |
Output is correct |
7 |
Incorrect |
4 ms |
4948 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
4948 KB |
Output is correct |
2 |
Correct |
3 ms |
4948 KB |
Output is correct |
3 |
Correct |
4 ms |
4948 KB |
Output is correct |
4 |
Correct |
3 ms |
4948 KB |
Output is correct |
5 |
Correct |
3 ms |
4948 KB |
Output is correct |
6 |
Correct |
3 ms |
4948 KB |
Output is correct |
7 |
Incorrect |
4 ms |
4948 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
78 ms |
17508 KB |
Output is correct |
2 |
Correct |
51 ms |
17488 KB |
Output is correct |
3 |
Correct |
80 ms |
23508 KB |
Output is correct |
4 |
Correct |
67 ms |
17484 KB |
Output is correct |
5 |
Correct |
72 ms |
18928 KB |
Output is correct |
6 |
Correct |
91 ms |
21868 KB |
Output is correct |
7 |
Correct |
75 ms |
18628 KB |
Output is correct |
8 |
Correct |
84 ms |
19392 KB |
Output is correct |
9 |
Correct |
90 ms |
16272 KB |
Output is correct |
10 |
Correct |
78 ms |
16644 KB |
Output is correct |
11 |
Correct |
54 ms |
13832 KB |
Output is correct |
12 |
Correct |
72 ms |
13628 KB |
Output is correct |
13 |
Correct |
65 ms |
14044 KB |
Output is correct |
14 |
Correct |
55 ms |
13780 KB |
Output is correct |
15 |
Correct |
47 ms |
14148 KB |
Output is correct |
16 |
Correct |
46 ms |
13724 KB |
Output is correct |
17 |
Correct |
8 ms |
10576 KB |
Output is correct |
18 |
Correct |
10 ms |
10704 KB |
Output is correct |
19 |
Correct |
8 ms |
10608 KB |
Output is correct |
20 |
Correct |
8 ms |
10572 KB |
Output is correct |
21 |
Correct |
9 ms |
10636 KB |
Output is correct |
22 |
Correct |
8 ms |
10636 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
5076 KB |
Output is correct |
2 |
Correct |
3 ms |
5076 KB |
Output is correct |
3 |
Correct |
4 ms |
5076 KB |
Output is correct |
4 |
Correct |
3 ms |
5332 KB |
Output is correct |
5 |
Correct |
3 ms |
5204 KB |
Output is correct |
6 |
Correct |
3 ms |
5204 KB |
Output is correct |
7 |
Correct |
3 ms |
5204 KB |
Output is correct |
8 |
Correct |
4 ms |
5204 KB |
Output is correct |
9 |
Correct |
3 ms |
5204 KB |
Output is correct |
10 |
Correct |
4 ms |
5140 KB |
Output is correct |
11 |
Correct |
3 ms |
5076 KB |
Output is correct |
12 |
Correct |
4 ms |
5076 KB |
Output is correct |
13 |
Correct |
3 ms |
5076 KB |
Output is correct |
14 |
Correct |
3 ms |
5076 KB |
Output is correct |
15 |
Correct |
3 ms |
5076 KB |
Output is correct |
16 |
Correct |
3 ms |
5076 KB |
Output is correct |
17 |
Correct |
3 ms |
5204 KB |
Output is correct |
18 |
Correct |
3 ms |
5204 KB |
Output is correct |
19 |
Correct |
3 ms |
5204 KB |
Output is correct |
20 |
Correct |
3 ms |
5204 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
89 ms |
17160 KB |
Output is correct |
2 |
Correct |
82 ms |
17100 KB |
Output is correct |
3 |
Correct |
90 ms |
17108 KB |
Output is correct |
4 |
Correct |
109 ms |
17120 KB |
Output is correct |
5 |
Correct |
97 ms |
17168 KB |
Output is correct |
6 |
Correct |
139 ms |
29556 KB |
Output is correct |
7 |
Correct |
146 ms |
25860 KB |
Output is correct |
8 |
Correct |
131 ms |
23580 KB |
Output is correct |
9 |
Correct |
103 ms |
21436 KB |
Output is correct |
10 |
Correct |
82 ms |
17316 KB |
Output is correct |
11 |
Correct |
116 ms |
17172 KB |
Output is correct |
12 |
Correct |
78 ms |
17112 KB |
Output is correct |
13 |
Correct |
75 ms |
17100 KB |
Output is correct |
14 |
Correct |
73 ms |
16832 KB |
Output is correct |
15 |
Correct |
83 ms |
16428 KB |
Output is correct |
16 |
Correct |
67 ms |
14900 KB |
Output is correct |
17 |
Correct |
74 ms |
19212 KB |
Output is correct |
18 |
Correct |
70 ms |
19588 KB |
Output is correct |
19 |
Correct |
70 ms |
20088 KB |
Output is correct |
20 |
Correct |
63 ms |
19076 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
5076 KB |
Output is correct |
2 |
Correct |
4 ms |
5076 KB |
Output is correct |
3 |
Incorrect |
4 ms |
5076 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
129 ms |
17080 KB |
Output is correct |
2 |
Correct |
110 ms |
16912 KB |
Output is correct |
3 |
Incorrect |
107 ms |
15200 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
4948 KB |
Output is correct |
2 |
Correct |
3 ms |
4948 KB |
Output is correct |
3 |
Correct |
4 ms |
4948 KB |
Output is correct |
4 |
Correct |
3 ms |
4948 KB |
Output is correct |
5 |
Correct |
3 ms |
4948 KB |
Output is correct |
6 |
Correct |
3 ms |
4948 KB |
Output is correct |
7 |
Incorrect |
4 ms |
4948 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
3 ms |
4948 KB |
Output is correct |
2 |
Correct |
3 ms |
4948 KB |
Output is correct |
3 |
Correct |
4 ms |
4948 KB |
Output is correct |
4 |
Correct |
3 ms |
4948 KB |
Output is correct |
5 |
Correct |
3 ms |
4948 KB |
Output is correct |
6 |
Correct |
3 ms |
4948 KB |
Output is correct |
7 |
Incorrect |
4 ms |
4948 KB |
Output isn't correct |
8 |
Halted |
0 ms |
0 KB |
- |