{ "data": { "question": { "questionId": "684", "questionFrontendId": "684", "boundTopicId": null, "title": "Redundant Connection", "titleSlug": "redundant-connection", "content": "

In this problem, a tree is an undirected graph that is connected and has no cycles.

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You are given a graph that started as a tree with n nodes labeled from 1 to n, with one additional edge added. The added edge has two different vertices chosen from 1 to n, and was not an edge that already existed. The graph is represented as an array edges of length n where edges[i] = [ai, bi] indicates that there is an edge between nodes ai and bi in the graph.

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Return an edge that can be removed so that the resulting graph is a tree of n nodes. If there are multiple answers, return the answer that occurs last in the input.

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Example 1:

\n\"\"\n
\nInput: edges = [[1,2],[1,3],[2,3]]\nOutput: [2,3]\n
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Example 2:

\n\"\"\n
\nInput: edges = [[1,2],[2,3],[3,4],[1,4],[1,5]]\nOutput: [1,4]\n
\n\n

 

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Constraints:

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Python 2.7.12.

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C# 10 with .NET 6 runtime

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