Method dfs

FindEventualSafeStates.java:15–28

(int node, int[][] graph, HashMap<Integer,Boolean> map)

        return res;
    }
    public boolean dfs(int node, int[][] graph, HashMap<Integer,Boolean> map){
        if(map.containsKey(node)){
            return map.get(node);
        }

        map.put(node,false);
        for(int neighbour : graph[node]){
            if(!dfs(neighbour, graph, map)){
                return false;
            }
        }
        map.put(node,true);
        return true;
    }
}