Find Eventual Safe States

There is a directed graph of `n` nodes with each node labeled from `0` to `n - 1`. The graph is represented by a **0-indexed** 2D integer array `graph` where `graph[i]` is an integer array of nodes adjacent to node `i`, meaning there is an edge from node `i` to each node in `graph[i]`. A node is a **terminal node** if there are no outgoing edges. A node is a **safe node** if every possible path starting from that node leads to a **terminal node** (or another safe node). Return _an array containing all the **safe nodes** of the graph_. The answer should be sorted in **ascending** order.   **Example 1:** **Input:** graph = [[1,2],[2,3],[5],[0],[5],[],[]] **Output:** [2,4,5,6] **Explanation:** The given graph is shown above. Nodes 5 and 6 are terminal nodes as there are no outgoing edges from either of them. Every path starting at nodes 2, 4, 5, and 6 all lead to either node 5 or 6. ``` **Example 2:** **Input:** graph = [[1,2,3,4],[1,2],[3,4],[0,4],[]] **Output:** [4] **Explanation:** Only node 4 is a terminal node, and every path starting at node 4 leads to node 4. ```   **Constraints:** - `n == graph.length` - `1 <= n <= 104` - `0 <= graph[i].length <= n` - `0 <= graph[i][j] <= n - 1` - `graph[i]` is sorted in a strictly increasing order. - The graph may contain self-loops. - The number of edges in the graph will be in the range `[1, 4 * 104]`.