{ "data": { "question": { "questionId": "2364", "questionFrontendId": "2246", "boundTopicId": null, "title": "Longest Path With Different Adjacent Characters", "titleSlug": "longest-path-with-different-adjacent-characters", "content": "

You are given a tree (i.e. a connected, undirected graph that has no cycles) rooted at node 0 consisting of n nodes numbered from 0 to n - 1. The tree is represented by a 0-indexed array parent of size n, where parent[i] is the parent of node i. Since node 0 is the root, parent[0] == -1.

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You are also given a string s of length n, where s[i] is the character assigned to node i.

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Return the length of the longest path in the tree such that no pair of adjacent nodes on the path have the same character assigned to them.

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\n

Example 1:

\n\"\"\n
\nInput: parent = [-1,0,0,1,1,2], s = "abacbe"\nOutput: 3\nExplanation: The longest path where each two adjacent nodes have different characters in the tree is the path: 0 -> 1 -> 3. The length of this path is 3, so 3 is returned.\nIt can be proven that there is no longer path that satisfies the conditions. \n
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Example 2:

\n\"\"\n
\nInput: parent = [-1,0,0,0], s = "aabc"\nOutput: 3\nExplanation: The longest path where each two adjacent nodes have different characters is the path: 2 -> 0 -> 3. The length of this path is 3, so 3 is returned.\n
\n\n

 

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Constraints:

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Most standard library headers are already included automatically for your convenience.

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OpenJDK 17. Java 8 features such as lambda expressions and stream API can be used.

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Python 2.7.12.

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C# 10 with .NET 6 runtime

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Node.js 16.13.2.

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Ruby 3.1

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Go 1.21

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Python 3.10.

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Scala 2.13.7.

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Kotlin 1.9.0.

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Rust 1.58.1

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PHP 8.1.

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