{ "data": { "question": { "questionId": "3439", "questionFrontendId": "3203", "boundTopicId": null, "title": "Find Minimum Diameter After Merging Two Trees", "titleSlug": "find-minimum-diameter-after-merging-two-trees", "content": "

There exist two undirected trees with n and m nodes, numbered from 0 to n - 1 and from 0 to m - 1, respectively. You are given two 2D integer arrays edges1 and edges2 of lengths n - 1 and m - 1, respectively, where edges1[i] = [ai, bi] indicates that there is an edge between nodes ai and bi in the first tree and edges2[i] = [ui, vi] indicates that there is an edge between nodes ui and vi in the second tree.

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You must connect one node from the first tree with another node from the second tree with an edge.

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Return the minimum possible diameter of the resulting tree.

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The diameter of a tree is the length of the longest path between any two nodes in the tree.

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Example 1:\"\"

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Input: edges1 = [[0,1],[0,2],[0,3]], edges2 = [[0,1]]

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Output: 3

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Explanation:

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We can obtain a tree of diameter 3 by connecting node 0 from the first tree with any node from the second tree.

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Example 2:

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Input: edges1 = [[0,1],[0,2],[0,3],[2,4],[2,5],[3,6],[2,7]], edges2 = [[0,1],[0,2],[0,3],[2,4],[2,5],[3,6],[2,7]]

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Output: 5

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Explanation:

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We can obtain a tree of diameter 5 by connecting node 0 from the first tree with node 0 from the second tree.

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Constraints:

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  2. The diameter of tree 2.
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