#include <bits/stdc++.h>
using namespace std;
int n, m;
typedef vector<int> vi;
typedef pair<int,int> ii;
struct node{
int depth = -1;
int low;
int parent;
bool vis = false;
bool isArti = false;
vi adj;
};
vector<unordered_set<int> > biconnected;
stack<int> s; ///this is only needed for biconnected components
///note: this will ignore single nodes with no edges
static node g[200005];
int rootChildren = 0;
void dfs(int u){
if(g[u].depth == -1) g[u].depth = g[g[u].parent].depth + 1;
g[u].low = g[u].depth;
g[u].vis = true;
for(int i = 0;i < g[u].adj.size();i++){
int v = g[u].adj[i];
if(!g[v].vis){
g[v].parent = u;
if(g[u].depth == 0) rootChildren++;
s.push(u); ///s traces the path of tree traversal
dfs(v);
g[u].low = min(g[u].low,g[v].low);
if(g[v].low >= g[u].depth){
g[u].isArti = true;
g[u].low = min(g[u].low,g[v].low);
unordered_set<int> newSet;
int nn;
biconnected.push_back(newSet); ///create new biconnected component
do{
assert(!s.empty());
nn = s.top();
s.pop();
biconnected.back().insert(nn);
}while(nn != u);
}
///if(g[v].low > g[u].depth{
///u,v is a bridge
///}
}
else if(v != g[u].parent){
g[u].low = min(g[u].low,g[v].low);
}
s.push(u);
}
}
struct node2{
long long sz;
long long dp = 0;
bool isArti = false;
bool vis = false;
int r;
int p = -1;
vi adj;
};
vector<node2> bct; ///block-cut tree
long long root = -1;
void dp(int u){
if(bct[u].vis) return;
bct[u].vis = true;
bct[u].dp = bct[u].sz;
bct[u].r = root;
for(int i = 0;i < bct[u].adj.size();i++){
int v = bct[u].adj[i];
if(bct[v].vis) continue;
bct[v].p = u;
dp(v);
bct[u].dp += bct[v].dp;
}
}
int main()
{
//freopen("i.txt","r",stdin);
cin >> n >> m;
ii edges[m];
for(int i = 0;i < m;i++){
int a, b;
cin >> a >> b;
a--;
b--;
g[a].adj.push_back(b);
g[b].adj.push_back(a);
edges[i] = ii(a,b);
}
for(int i = 0;i < n;i++){
if(!g[i].vis){
rootChildren = 0;
g[i].depth = 0;
dfs(i);
if(rootChildren > 1) g[i].isArti = true;
else g[i].isArti = false; ///this line is needed
}
}
unordered_map<int,int> artis;
for(int i = 0;i < n;i++){
if(g[i].isArti){
artis[i] = bct.size();
node2 nn;
nn.sz = 1;
nn.isArti = true;
bct.push_back(nn);
}
}
for(int i = 0;i < biconnected.size();i++){
node2 nn;
nn.sz = biconnected[i].size();
nn.isArti = false;
for(unordered_set<int>::iterator it = biconnected[i].begin();it != biconnected[i].end();it++){
//cout << *it << " ";
if(artis.find(*it) != artis.end()){
nn.adj.push_back(artis[*it]);
bct[artis[*it]].adj.push_back(bct.size());
nn.sz--;
}
}
bct.push_back(nn);
//cout << "\n";
}
for(int i = 0;i < bct.size();i++){
root = i;
dp(i);
}
/*
for(int i = 0;i < bct.size();i++){
cout << i << " " << bct[i].sz << " " << bct[i].dp << " " << bct[i].isArti << "| ";
for(int j = 0;j < bct[i].adj.size();j++){
cout << bct[i].adj[j] << " ";
}
cout << "\n";
}
*/
long long ans = 0ll;
for(int i = 0;i < bct.size();i++){
vector<long long> branches;
vector<long long> branchStart;
long long total = 0ll;
for(int j = 0;j < bct[i].adj.size();j++){
if(bct[i].adj[j] != bct[i].p){
branches.push_back(bct[bct[i].adj[j]].dp);
branchStart.push_back(bct[bct[i].adj[j]].sz);
}
}
if(bct[i].p >= 0){
branches.push_back(bct[bct[i].r].dp - bct[i].dp);
branchStart.push_back(bct[bct[i].p].sz);
}
for(int j = 0;j < branches.size();j++) total += branches[j];
/*
long long extra = 0, extra2 = 0;
if(!bct[i].isArti) extra = max(0ll,(long long)(bct[i].adj.size())-2);
if(!bct[i].isArti) extra2 = max(0ll,(long long)(bct[i].adj.size())-1);
for(int j = 0;j < branches.size();j++){
//cout << i << " " << branches[j] << "\n";
///branch1 to self or neighbor articulation point to branch2
ans += branches[j] * (total - branches[j]) * (bct[i].sz + extra);
///branch to self to self or self to self to branch
ans += 2 * (bct[i].sz) * (bct[i].sz + extra2 - 1) * branches[j];
///self to arti to another branch
//if(!bct[i].isArti){
// ans += 2ll * (bct[i].sz) * branches[j] * (bct[i].adj.size() - 1);
//}
if(bct[i].isArti){
///direct branch to self to same branch(not reverse) or its reverse
ans += 2ll * bct[i].sz * branchStart[j] * (branches[j] - branchStart[j]);
///direct branch to self to direct or its reverse
ans += bct[i].sz * (branchStart[j]) * (branchStart[j] - 1);
}
}
///self to self to self
ans += (bct[i].sz) * (bct[i].sz - 1) * (bct[i].sz - 2);
*/
long long sz = bct[i].sz;
if(!bct[i].isArti){
ans += sz * (sz - 1) * (sz + bct[i].adj.size() - 2);
ans += 2ll * sz * (sz + bct[i].adj.size() - 2) * total;
}
for(int j = 0;j < branches.size();j++){
long long extra = 0, extra2 = 0;
if(!bct[i].isArti) extra = max(0ll,(long long)(bct[i].adj.size())-2);
ans += branches[j] * (total - branches[j]) * (bct[i].sz + extra);
}
//if(!bct[i].isArti) ans += (bct[i].sz) * (bct[i].sz - 1) * (bct[i].adj.size());
//cout << i << " " << ans << "\n";
}
cout << ans;
}
/*
8 7
8 5
8 1
7 5
8 6
3 1
3 2
8 3
*/
/*
10 12
6 4
10 3
4 2
4 1
4 3
6 5
9 1
9 4
2 1
9 3
8 5
7 2
*/
Compilation message
count_triplets.cpp: In function 'void dfs(int)':
count_triplets.cpp:25:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0;i < g[u].adj.size();i++){
~~^~~~~~~~~~~~~~~~~
count_triplets.cpp: In function 'void dp(int)':
count_triplets.cpp:74:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0;i < bct[u].adj.size();i++){
~~^~~~~~~~~~~~~~~~~~~
count_triplets.cpp: In function 'int main()':
count_triplets.cpp:118:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0;i < biconnected.size();i++){
~~^~~~~~~~~~~~~~~~~~~~
count_triplets.cpp:133:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0;i < bct.size();i++){
~~^~~~~~~~~~~~
count_triplets.cpp:147:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i = 0;i < bct.size();i++){
~~^~~~~~~~~~~~
count_triplets.cpp:151:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j = 0;j < bct[i].adj.size();j++){
~~^~~~~~~~~~~~~~~~~~~
count_triplets.cpp:161:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j = 0;j < branches.size();j++) total += branches[j];
~~^~~~~~~~~~~~~~~~~
count_triplets.cpp:199:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j = 0;j < branches.size();j++){
~~^~~~~~~~~~~~~~~~~
count_triplets.cpp:200:34: warning: unused variable 'extra2' [-Wunused-variable]
long long extra = 0, extra2 = 0;
^~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
8192 KB |
Output is correct |
2 |
Correct |
11 ms |
8192 KB |
Output is correct |
3 |
Correct |
11 ms |
8192 KB |
Output is correct |
4 |
Correct |
10 ms |
8192 KB |
Output is correct |
5 |
Correct |
10 ms |
8064 KB |
Output is correct |
6 |
Correct |
10 ms |
8192 KB |
Output is correct |
7 |
Correct |
10 ms |
8192 KB |
Output is correct |
8 |
Correct |
10 ms |
8192 KB |
Output is correct |
9 |
Correct |
10 ms |
8192 KB |
Output is correct |
10 |
Correct |
10 ms |
8192 KB |
Output is correct |
11 |
Correct |
11 ms |
8192 KB |
Output is correct |
12 |
Correct |
11 ms |
8192 KB |
Output is correct |
13 |
Correct |
9 ms |
8080 KB |
Output is correct |
14 |
Correct |
9 ms |
8192 KB |
Output is correct |
15 |
Correct |
12 ms |
8192 KB |
Output is correct |
16 |
Correct |
10 ms |
8192 KB |
Output is correct |
17 |
Correct |
9 ms |
8192 KB |
Output is correct |
18 |
Correct |
10 ms |
8192 KB |
Output is correct |
19 |
Correct |
11 ms |
8080 KB |
Output is correct |
20 |
Correct |
10 ms |
8192 KB |
Output is correct |
21 |
Correct |
10 ms |
8192 KB |
Output is correct |
22 |
Incorrect |
10 ms |
8192 KB |
Output isn't correct |
23 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
8192 KB |
Output is correct |
2 |
Correct |
11 ms |
8192 KB |
Output is correct |
3 |
Correct |
11 ms |
8192 KB |
Output is correct |
4 |
Correct |
10 ms |
8192 KB |
Output is correct |
5 |
Correct |
10 ms |
8064 KB |
Output is correct |
6 |
Correct |
10 ms |
8192 KB |
Output is correct |
7 |
Correct |
10 ms |
8192 KB |
Output is correct |
8 |
Correct |
10 ms |
8192 KB |
Output is correct |
9 |
Correct |
10 ms |
8192 KB |
Output is correct |
10 |
Correct |
10 ms |
8192 KB |
Output is correct |
11 |
Correct |
11 ms |
8192 KB |
Output is correct |
12 |
Correct |
11 ms |
8192 KB |
Output is correct |
13 |
Correct |
9 ms |
8080 KB |
Output is correct |
14 |
Correct |
9 ms |
8192 KB |
Output is correct |
15 |
Correct |
12 ms |
8192 KB |
Output is correct |
16 |
Correct |
10 ms |
8192 KB |
Output is correct |
17 |
Correct |
9 ms |
8192 KB |
Output is correct |
18 |
Correct |
10 ms |
8192 KB |
Output is correct |
19 |
Correct |
11 ms |
8080 KB |
Output is correct |
20 |
Correct |
10 ms |
8192 KB |
Output is correct |
21 |
Correct |
10 ms |
8192 KB |
Output is correct |
22 |
Incorrect |
10 ms |
8192 KB |
Output isn't correct |
23 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
243 ms |
32456 KB |
Output is correct |
2 |
Correct |
236 ms |
32564 KB |
Output is correct |
3 |
Correct |
329 ms |
40212 KB |
Output is correct |
4 |
Correct |
332 ms |
36552 KB |
Output is correct |
5 |
Correct |
299 ms |
36088 KB |
Output is correct |
6 |
Correct |
398 ms |
39792 KB |
Output is correct |
7 |
Correct |
397 ms |
38972 KB |
Output is correct |
8 |
Correct |
378 ms |
40392 KB |
Output is correct |
9 |
Correct |
414 ms |
37560 KB |
Output is correct |
10 |
Correct |
370 ms |
35776 KB |
Output is correct |
11 |
Correct |
306 ms |
31552 KB |
Output is correct |
12 |
Correct |
264 ms |
31320 KB |
Output is correct |
13 |
Correct |
179 ms |
30912 KB |
Output is correct |
14 |
Correct |
237 ms |
30564 KB |
Output is correct |
15 |
Correct |
158 ms |
24388 KB |
Output is correct |
16 |
Correct |
210 ms |
24132 KB |
Output is correct |
17 |
Correct |
11 ms |
8192 KB |
Output is correct |
18 |
Correct |
15 ms |
8192 KB |
Output is correct |
19 |
Correct |
11 ms |
8192 KB |
Output is correct |
20 |
Correct |
11 ms |
8192 KB |
Output is correct |
21 |
Correct |
11 ms |
8192 KB |
Output is correct |
22 |
Correct |
11 ms |
8192 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
14 ms |
8576 KB |
Output is correct |
2 |
Correct |
13 ms |
8592 KB |
Output is correct |
3 |
Correct |
13 ms |
8576 KB |
Output is correct |
4 |
Correct |
14 ms |
8704 KB |
Output is correct |
5 |
Correct |
12 ms |
8568 KB |
Output is correct |
6 |
Correct |
14 ms |
8576 KB |
Output is correct |
7 |
Correct |
11 ms |
8704 KB |
Output is correct |
8 |
Correct |
15 ms |
8576 KB |
Output is correct |
9 |
Correct |
13 ms |
8576 KB |
Output is correct |
10 |
Correct |
13 ms |
8576 KB |
Output is correct |
11 |
Correct |
11 ms |
8576 KB |
Output is correct |
12 |
Correct |
12 ms |
8572 KB |
Output is correct |
13 |
Correct |
11 ms |
8572 KB |
Output is correct |
14 |
Correct |
11 ms |
8448 KB |
Output is correct |
15 |
Correct |
13 ms |
8448 KB |
Output is correct |
16 |
Correct |
11 ms |
8320 KB |
Output is correct |
17 |
Correct |
10 ms |
8448 KB |
Output is correct |
18 |
Correct |
11 ms |
8448 KB |
Output is correct |
19 |
Correct |
13 ms |
8448 KB |
Output is correct |
20 |
Correct |
10 ms |
8448 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
467 ms |
48728 KB |
Output is correct |
2 |
Correct |
371 ms |
48824 KB |
Output is correct |
3 |
Correct |
396 ms |
48796 KB |
Output is correct |
4 |
Correct |
406 ms |
48796 KB |
Output is correct |
5 |
Correct |
441 ms |
48824 KB |
Output is correct |
6 |
Correct |
528 ms |
57272 KB |
Output is correct |
7 |
Correct |
435 ms |
54428 KB |
Output is correct |
8 |
Correct |
428 ms |
52948 KB |
Output is correct |
9 |
Correct |
374 ms |
51632 KB |
Output is correct |
10 |
Correct |
400 ms |
48820 KB |
Output is correct |
11 |
Correct |
396 ms |
48780 KB |
Output is correct |
12 |
Correct |
393 ms |
48756 KB |
Output is correct |
13 |
Correct |
374 ms |
48756 KB |
Output is correct |
14 |
Correct |
337 ms |
47188 KB |
Output is correct |
15 |
Correct |
332 ms |
37948 KB |
Output is correct |
16 |
Correct |
156 ms |
29436 KB |
Output is correct |
17 |
Correct |
222 ms |
40624 KB |
Output is correct |
18 |
Correct |
239 ms |
40600 KB |
Output is correct |
19 |
Correct |
269 ms |
40368 KB |
Output is correct |
20 |
Correct |
325 ms |
40252 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
12 ms |
8576 KB |
Output is correct |
2 |
Correct |
14 ms |
8576 KB |
Output is correct |
3 |
Correct |
15 ms |
8448 KB |
Output is correct |
4 |
Correct |
13 ms |
8576 KB |
Output is correct |
5 |
Correct |
12 ms |
8320 KB |
Output is correct |
6 |
Correct |
12 ms |
8320 KB |
Output is correct |
7 |
Correct |
12 ms |
8320 KB |
Output is correct |
8 |
Correct |
11 ms |
8292 KB |
Output is correct |
9 |
Correct |
17 ms |
8320 KB |
Output is correct |
10 |
Correct |
12 ms |
8320 KB |
Output is correct |
11 |
Correct |
10 ms |
8320 KB |
Output is correct |
12 |
Correct |
11 ms |
8576 KB |
Output is correct |
13 |
Correct |
12 ms |
8576 KB |
Output is correct |
14 |
Correct |
12 ms |
8576 KB |
Output is correct |
15 |
Correct |
11 ms |
8576 KB |
Output is correct |
16 |
Correct |
17 ms |
8448 KB |
Output is correct |
17 |
Correct |
14 ms |
8448 KB |
Output is correct |
18 |
Correct |
14 ms |
8448 KB |
Output is correct |
19 |
Correct |
12 ms |
8448 KB |
Output is correct |
20 |
Correct |
11 ms |
8320 KB |
Output is correct |
21 |
Correct |
10 ms |
8448 KB |
Output is correct |
22 |
Correct |
10 ms |
8448 KB |
Output is correct |
23 |
Correct |
11 ms |
8448 KB |
Output is correct |
24 |
Correct |
12 ms |
8448 KB |
Output is correct |
25 |
Correct |
8 ms |
8192 KB |
Output is correct |
26 |
Correct |
10 ms |
8192 KB |
Output is correct |
27 |
Correct |
12 ms |
8192 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
382 ms |
48824 KB |
Output is correct |
2 |
Correct |
458 ms |
48740 KB |
Output is correct |
3 |
Correct |
410 ms |
47560 KB |
Output is correct |
4 |
Correct |
326 ms |
34116 KB |
Output is correct |
5 |
Correct |
323 ms |
27584 KB |
Output is correct |
6 |
Correct |
306 ms |
24668 KB |
Output is correct |
7 |
Correct |
261 ms |
24264 KB |
Output is correct |
8 |
Correct |
223 ms |
20684 KB |
Output is correct |
9 |
Correct |
225 ms |
20444 KB |
Output is correct |
10 |
Correct |
309 ms |
19104 KB |
Output is correct |
11 |
Correct |
213 ms |
18060 KB |
Output is correct |
12 |
Correct |
186 ms |
17400 KB |
Output is correct |
13 |
Correct |
176 ms |
17464 KB |
Output is correct |
14 |
Correct |
178 ms |
20668 KB |
Output is correct |
15 |
Correct |
501 ms |
53980 KB |
Output is correct |
16 |
Correct |
388 ms |
51640 KB |
Output is correct |
17 |
Correct |
480 ms |
44856 KB |
Output is correct |
18 |
Correct |
424 ms |
42296 KB |
Output is correct |
19 |
Correct |
387 ms |
34188 KB |
Output is correct |
20 |
Correct |
320 ms |
33984 KB |
Output is correct |
21 |
Correct |
408 ms |
34036 KB |
Output is correct |
22 |
Correct |
341 ms |
32388 KB |
Output is correct |
23 |
Correct |
278 ms |
27080 KB |
Output is correct |
24 |
Correct |
326 ms |
39740 KB |
Output is correct |
25 |
Correct |
374 ms |
39768 KB |
Output is correct |
26 |
Correct |
316 ms |
37484 KB |
Output is correct |
27 |
Correct |
294 ms |
37176 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
8192 KB |
Output is correct |
2 |
Correct |
11 ms |
8192 KB |
Output is correct |
3 |
Correct |
11 ms |
8192 KB |
Output is correct |
4 |
Correct |
10 ms |
8192 KB |
Output is correct |
5 |
Correct |
10 ms |
8064 KB |
Output is correct |
6 |
Correct |
10 ms |
8192 KB |
Output is correct |
7 |
Correct |
10 ms |
8192 KB |
Output is correct |
8 |
Correct |
10 ms |
8192 KB |
Output is correct |
9 |
Correct |
10 ms |
8192 KB |
Output is correct |
10 |
Correct |
10 ms |
8192 KB |
Output is correct |
11 |
Correct |
11 ms |
8192 KB |
Output is correct |
12 |
Correct |
11 ms |
8192 KB |
Output is correct |
13 |
Correct |
9 ms |
8080 KB |
Output is correct |
14 |
Correct |
9 ms |
8192 KB |
Output is correct |
15 |
Correct |
12 ms |
8192 KB |
Output is correct |
16 |
Correct |
10 ms |
8192 KB |
Output is correct |
17 |
Correct |
9 ms |
8192 KB |
Output is correct |
18 |
Correct |
10 ms |
8192 KB |
Output is correct |
19 |
Correct |
11 ms |
8080 KB |
Output is correct |
20 |
Correct |
10 ms |
8192 KB |
Output is correct |
21 |
Correct |
10 ms |
8192 KB |
Output is correct |
22 |
Incorrect |
10 ms |
8192 KB |
Output isn't correct |
23 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
11 ms |
8192 KB |
Output is correct |
2 |
Correct |
11 ms |
8192 KB |
Output is correct |
3 |
Correct |
11 ms |
8192 KB |
Output is correct |
4 |
Correct |
10 ms |
8192 KB |
Output is correct |
5 |
Correct |
10 ms |
8064 KB |
Output is correct |
6 |
Correct |
10 ms |
8192 KB |
Output is correct |
7 |
Correct |
10 ms |
8192 KB |
Output is correct |
8 |
Correct |
10 ms |
8192 KB |
Output is correct |
9 |
Correct |
10 ms |
8192 KB |
Output is correct |
10 |
Correct |
10 ms |
8192 KB |
Output is correct |
11 |
Correct |
11 ms |
8192 KB |
Output is correct |
12 |
Correct |
11 ms |
8192 KB |
Output is correct |
13 |
Correct |
9 ms |
8080 KB |
Output is correct |
14 |
Correct |
9 ms |
8192 KB |
Output is correct |
15 |
Correct |
12 ms |
8192 KB |
Output is correct |
16 |
Correct |
10 ms |
8192 KB |
Output is correct |
17 |
Correct |
9 ms |
8192 KB |
Output is correct |
18 |
Correct |
10 ms |
8192 KB |
Output is correct |
19 |
Correct |
11 ms |
8080 KB |
Output is correct |
20 |
Correct |
10 ms |
8192 KB |
Output is correct |
21 |
Correct |
10 ms |
8192 KB |
Output is correct |
22 |
Incorrect |
10 ms |
8192 KB |
Output isn't correct |
23 |
Halted |
0 ms |
0 KB |
- |