| 7 | if (!visited[v = adj[u][i]]) scc_dfs(adj, v); |
| 8 | order.push_back(u); } |
| 9 | pair<union_find, vi> scc(const vvi &adj) { |
| 10 | int n = size(adj), u, v; |
| 11 | order.clear(); |
| 12 | union_find uf(n); vi dag; vvi rev(n); |
| 13 | rep(i,0,n) rep(j,0,size(adj[i])) rev[adj[i][j]].push_back(i); |
| 14 | visited.resize(n); |
| 15 | fill(visited.begin(), visited.end(), false); |
| 16 | rep(i,0,n) if (!visited[i]) scc_dfs(rev, i); |
| 17 | fill(visited.begin(), visited.end(), false); |
| 18 | stack<int> S; |
| 19 | for (int i = n-1; i >= 0; i--) { |
| 20 | if (visited[order[i]]) continue; |
| 21 | S.push(order[i]), dag.push_back(order[i]); |
| 22 | while (!S.empty()) { |
| 23 | visited[u = S.top()] = true, S.pop(); |
| 24 | uf.unite(u, order[i]); |
| 25 | rep(j,0,size(adj[u])) |
| 26 | if (!visited[v = adj[u][j]]) S.push(v); } } |
| 27 | return pair<union_find, vi>(uf, dag); } |
| 28 | // vim: cc=60 ts=2 sts=2 sw=2: |