int main() {
/* Build graph */
dfs_num.assign(n, DFS_WHITE);
dfs_low.assign(n,0);
visited.assign(n, 0);
dfsNumberCounter = numSCC = 0;
for (int i = 0; i < n; i++)
if (dfs_num[i] == DFS_WHITE)
tarjanSCC(i);
return 0;
}
void tarjanSCC(int u) {
dfs_low[u] = dfs_num[u] = dfsNumberCounter++;
S.push_back(u);
visited[u] = 1;
for (int j = 0; j < g[u].size(); j++) {
int v = g[u][j];
if (dfs_num[v] == DFS_WHITE) tarjanSCC(v);
if (visited[v]) dfs_low[u] = min(dfs_low[u], dfs_low[v]);
}
if (dfs_low[u] == dfs_num[u]) {
cout << "SCC " << ++numSCC << ":";
while (1) {
int v = S.back();
S.pop_back();
visited[v] = 0;
cout << " " << v;
if (u == v) break;
}
cout << endl;
}
}
void tarjanSCC(int u){
int v;
dfs_low[u] = dfs_num[u] = counter++;
S.push_back(u);
vis[u] = 1;
for(int j=0; j<nadj[u]; j++){
v = adj[u][j];
if(dfs_num[v]==-1)
tarjanSCC(v);
if(vis[u])
dfs_low[u] = min(dfs_low[u],dfs_low[v]);
}
if(dfs_low[u]==dfs_num[u]){
printf("SCC %d\n",++numSCC);
while(1){
v = s.back(); S.pop_back(); visited[v]=0;
printf(" %d",v);
if(u==v) break;
}
printf("\n");
}
}
