{ "data": { "question": { "questionId": "820", "questionFrontendId": "802", "boundTopicId": null, "title": "Find Eventual Safe States", "titleSlug": "find-eventual-safe-states", "content": "

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].

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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.

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Return an array containing all the safe nodes of the graph. The answer should be sorted in ascending order.

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Example 1:

\n\"Illustration\n
\nInput: graph = [[1,2],[2,3],[5],[0],[5],[],[]]\nOutput: [2,4,5,6]\nExplanation: The given graph is shown above.\nNodes 5 and 6 are terminal nodes as there are no outgoing edges from either of them.\nEvery path starting at nodes 2, 4, 5, and 6 all lead to either node 5 or 6.
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Example 2:

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\nInput: graph = [[1,2,3,4],[1,2],[3,4],[0,4],[]]\nOutput: [4]\nExplanation:\nOnly node 4 is a terminal node, and every path starting at node 4 leads to node 4.\n
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Constraints:

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