Method dfs

java/0802-find-eventual-safe-states.java:12–24

(int[][] graph, int src, HashMap<Integer, Boolean> safe)

    }

    private boolean dfs(int[][] graph, int src, HashMap<Integer, Boolean> safe) {
        if (safe.containsKey(src))
            return safe.get(src);

        safe.put(src, false);

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