#include <bits/stdc++.h>
using namespace std;
typedef pair<int, int> pii;
typedef long long LL;
vector<pii> g[100005];
set<int> gs[100005];
bool idx[200005];
int low[100005], vis[100005], p[100005], sz[100005], T = 1;
void dfs1(int u, int p){
vis[u] = low[u] = T++;
for(int i=0;i<g[u].size();i++){
int v = g[u][i].first;
if(v == p) continue;
if(vis[v]) low[u] = min(low[u], vis[v]);
else{
dfs1(v, u);
low[u] = min(low[u], low[v]);
if(low[v] > vis[u]) idx[g[u][i].second] = 1;
}
}
}
int root(int a){
while(p[a] != a){
p[a] = p[p[a]];
a = p[a];
}
return a;
}
bool merge(int a, int b){
a = root(a), b = root(b);
if(a == b) return 0;
sz[b] += sz[a];
p[a] = b;
return 1;
}
LL s[100005], sc[100005];
LL ans = 0;
void dfs2(int u, int p){
printf("U = %d\n", u);
vis[u] = 1;
for(set<int>::iterator its=gs[u].begin();its != gs[u].end();its++){
int v = *its;
if(v == p) continue;
dfs2(v, u);
ans += (LL)sc[v]*sz[u]; // f
if(sz[u] > 1) ans += (LL)s[v]*(sz[u]-1 + (LL)(sz[u]-1)*(sz[u]-2)); // cf
ans += (LL)sc[v]*s[u]; // f
ans += (LL)s[v]*sc[u]; // cf
s[u] += s[v];
sc[u] += sc[v];
sc[u] += (LL)s[v]*sz[u];
}
s[u] += sz[u];
sc[u] += (LL)(sz[u]-1)*(sz[u]-1);
}
int main(){
int n, m;
scanf("%d%d", &n, &m);
for(int i=0;i<m;i++){
int a, b;
scanf("%d%d", &a, &b);
g[a].push_back(pii(b, i));
g[b].push_back(pii(a, i));
}
for(int i=1;i<=n;i++){
if(vis[i]) continue;
dfs1(i, 0);
}
for(int i=1;i<=n;i++) p[i] = i, sz[i] = 1;
for(int i=1;i<=n;i++){
for(int j=0;j<g[i].size();j++){
int v = g[i][j].first, edge = g[i][j].second;
if(!idx[edge]){
merge(i, v);
}
}
}
int r = 0;
for(int i=1;i<=n;i++){
for(int j=0;j<g[i].size();j++){
int v = g[i][j].first, edge = g[i][j].second;
if(!idx[edge]) continue;
if(root(i) == root(v)) continue;
gs[root(i)].insert(root(v));
gs[root(v)].insert(root(i));
}
}
memset(vis, 0, sizeof(vis));
for(int i=1;i<=n;i++){
if(vis[i]) continue;
if(root(i) == i) dfs2(i, 0);
}
ans *= 2;
for(int i=1;i<=n;i++){
if(root(i) == i){
ans += (LL)sz[i]*(sz[i]-1)*(sz[i]-2);
}
}
printf("%lld\n", ans);
}
Compilation message
count_triplets.cpp: In function 'void dfs1(int, int)':
count_triplets.cpp:12:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0;i<g[u].size();i++){
~^~~~~~~~~~~~
count_triplets.cpp: In function 'int main()':
count_triplets.cpp:79:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j=0;j<g[i].size();j++){
~^~~~~~~~~~~~
count_triplets.cpp:88:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j=0;j<g[i].size();j++){
~^~~~~~~~~~~~
count_triplets.cpp:86:6: warning: unused variable 'r' [-Wunused-variable]
int r = 0;
^
count_triplets.cpp:66:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d", &n, &m);
~~~~~^~~~~~~~~~~~~~~~
count_triplets.cpp:69:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d", &a, &b);
~~~~~^~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
7800 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
7800 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
112 ms |
20024 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
10 ms |
20024 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
226 ms |
24760 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
11 ms |
24760 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
247 ms |
24932 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
7800 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
9 ms |
7800 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
