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.

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]`.