You are given an integer n and an undirected graph with n nodes labeled from 0 to n - 1 and a 2D array edges, where edges[i] = [ui, vi] indicates an edge between nodes ui and vi.
You are also given a string label of length n, where label[i] is the character associated with node i.
You may start at any node and move to any adjacent node, visiting each node at most once.
\n\nReturn the maximum possible length of a palindrome that can be formed by visiting a set of unique nodes along a valid path.
\n\n\n
Example 1:
\n\nInput: n = 3, edges = [[0,1],[1,2]], label = "aba"
\n\nOutput: 3
\n\nExplanation:
\n\n![](\"https://assets.leetcode.com/uploads/2025/06/13/screenshot-2025-06-13-at-230714.png\")
0 → 1 → 2 forming string "aba".Example 2:
\n\nInput: n = 3, edges = [[0,1],[0,2]], label = "abc"
\n\nOutput: 1
\n\nExplanation:
\n\n![](\"https://assets.leetcode.com/uploads/2025/06/13/screenshot-2025-06-13-at-230017.png\")
Example 3:
\n\nInput: n = 4, edges = [[0,2],[0,3],[3,1]], label = "bbac"
\n\nOutput: 3
\n\nExplanation:
\n\n![](\"https://assets.leetcode.com/uploads/2025/06/13/screenshot-2025-06-13-at-230508.png\")
0 → 3 → 1, forming string "bcb".\n
Constraints:
\n\n1 <= n <= 14n - 1 <= edges.length <= n * (n - 1) / 2edges[i] == [ui, vi]0 <= ui, vi <= n - 1ui != vilabel.length == nlabel consists of lowercase English letters.给你一个整数 n 和一个包含 n 个节点的 无向图 ，节点编号从 0 到 n - 1，以及一个二维数组 edges，其中 edges[i] = [ui, vi] 表示节点 ui 和节点 vi 之间有一条边。
同时给你一个长度为 n 的字符串 label，其中 label[i] 是与节点 i 关联的字符。
你可以从任意节点开始，移动到任意相邻节点，每个节点 最多 访问一次。
\n\n返回通过访问一条路径，路径中 不包含重复 节点，所能形成的 最长回文串 的长度。
\n\n回文串 是指正着读和反着读相同的字符串。
\n\n\n\n
示例 1：
\n\n输入： n = 3, edges = [[0,1],[1,2]], label = \"aba\"
\n\n输出： 3
\n\n解释：
\n\n
0 → 1 → 2，形成字符串 \"aba\"。示例 2：
\n\n输入： n = 3, edges = [[0,1],[0,2]], label = \"abc\"
\n\n输出： 1
\n\n解释：
\n\n
示例 3：
\n\n输入： n = 4, edges = [[0,2],[0,3],[3,1]], label = \"bbac\"
\n\n输出： 3
\n\n解释：
\n\n
0 → 3 → 1，形成字符串 \"bcb\"。\n\n
提示:
\n\n1 <= n <= 14n - 1 <= edges.length <= n * (n - 1) / 2edges[i] == [ui, vi]0 <= ui, vi <= n - 1ui != vilabel.length == nlabel 只包含小写英文字母。mask.",
"Before adding new endpoints to the current palindrome, ensure their labels match the labels at the previous endpoints prev_l and prev_r.",
"Memoize each state as dp[mask][prev_l][prev_r], representing the maximum palindrome length achievable using the set of visited nodes in mask with current endpoints at prev_l and prev_r."
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"sampleTestCase": "3\n[[0,1],[1,2]]\n\"aba\"",
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"exampleTestcases": "3\n[[0,1],[1,2]]\n\"aba\"\n3\n[[0,1],[0,2]]\n\"abc\"\n4\n[[0,2],[0,3],[3,1]]\n\"bbac\"",
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