CycleDetection

[aoyuanbo]

Whether or not there is a cycle, this program always returns true after running ` for (Integer neighbor : graph.getNeighbors(start)) {

        if(visited.contains(neighbor) && !exited.contains(neighbor)) return true;

        if(!visited.contains(neighbor) && dfs(neighbor)) return true;
    }`

[sherxon]

Can you give any sample directed graph that returns true if there is no cycle?

[aoyuanbo]

I know what happened, I use the undirected graph.