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‎README.md

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@@ -23,6 +23,7 @@ Your ideas/fixes/algorithms are more than welcome!
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| # | Title | Solutions | Time | Space | Difficulty | Tag | Notes
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|-----|----------------|---------------|---------------|---------------|-------------|--------------|-----
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|690|[Employee Importance](https://leetcode.com/problems/employee-importance/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_690.java) | O(n) | O(h) | Easy | DFS
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|687|[Longest Univalue Path](https://leetcode.com/problems/longest-univalue-path/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_687.java) | O(n) | O(h) | Easy | DFS
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|682|[Baseball Game](https://leetcode.com/problems/baseball-game/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_682.java) | O(n) | O(1) | Easy |
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|680|[Valid Palindrome II](https://leetcode.com/problems/valid-palindrome-ii/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_680.java) | O(n) | O(1) | Easy | String
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|679|[24 Game](https://leetcode.com/problems/24-game/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_679.java) | O(1) (Upper bound 9216)| O(1) | Hard | Recursion

‎src/main/java/com/fishercoder/solutions/_687.java

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package com.fishercoder.solutions;
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import com.fishercoder.common.classes.TreeNode;
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/**
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* 687. Longest Univalue Path
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*
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* Given a binary tree, find the length of the longest path where each node in the path has the same value.
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* This path may or may not pass through the root.
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Note: The length of path between two nodes is represented by the number of edges between them.
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Example 1:
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Input:
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5
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/ \
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4 5
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/ \ \
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1 1 5
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Output:
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2
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Example 2:
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Input:
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1
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/ \
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4 5
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/ \ \
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4 4 5
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Output:
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2
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Note: The given binary tree has not more than 10000 nodes. The height of the tree is not more than 1000.
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*/
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public class _687 {
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public static class Solution1 {
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public int longestUnivaluePath(TreeNode root) {
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int[] result = new int[1];
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if (root != null) {
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dfs(root, result);
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}
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return result[0];
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}
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private int dfs(TreeNode root, int[] result) {
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int leftPath = root.left == null ? 0 : dfs(root.left, result);
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int rightPath = root.right == null ? 0 : dfs(root.right, result);
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int leftResult = (root.left != null && root.left.val == root.val) ? leftPath + 1 : 0;
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int rightResult = (root.right != null && root.right.val == root.val) ? rightPath + 1 : 0;
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result[0] = Math.max(result[0], leftResult + rightResult);
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return Math.max(leftResult, rightResult);
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}
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}
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}

‎src/test/java/com/fishercoder/_687Test.java

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package com.fishercoder;
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import com.fishercoder.common.classes.TreeNode;
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import com.fishercoder.common.utils.TreeUtils;
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import com.fishercoder.solutions._687;
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import org.junit.Before;
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import org.junit.Test;
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import java.util.Arrays;
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import static org.junit.Assert.assertEquals;
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public class _687Test {
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private static _687.Solution1 solution1;
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private static TreeNode root;
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@Before
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public void setup() {
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solution1 = new _687.Solution1();
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}
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@Test
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public void test1() {
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root = TreeUtils.constructBinaryTree(Arrays.asList(5, 4, 5, 1, 1, null, 5));
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assertEquals(2, solution1.longestUnivaluePath(root));
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}
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@Test
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public void test2() {
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root = TreeUtils.constructBinaryTree(Arrays.asList(1, 4, 5, 4, 4, null, 5));
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TreeUtils.printBinaryTree(root);
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assertEquals(2, solution1.longestUnivaluePath(root));
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}
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@Test
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public void test3() {
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root = TreeUtils.constructBinaryTree(Arrays.asList(1, 1, 5, 1, 1, null, 5, null, 1, 1));
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TreeUtils.printBinaryTree(root);
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assertEquals(4, solution1.longestUnivaluePath(root));
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}
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@Test
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public void test4() {
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root = TreeUtils.constructBinaryTree(Arrays.asList(1, 5, 8, 9, 7, 7, 8, 1, 4, 8, 1, 9, 0, 8, 7, 1, 7, 4, 2, 9, 8, 2, 4, null, null, 9, null, null, null, 6, 0, 9, 4, 1, 0, 1, 8, 9, 0, 1, 8, 9, 1, 0, 9, 6, 2, 5, null, 2, 3, 0, 2, 4, 8, 8, 8, 5, 0, 0, 9, 4, 9, 1, null, 0, 7, 2, 2, 3, null, 6, 1, 0, 8, 9, 9, 9, 4, 8, 4, 3, 4, 4, 0, null, null, 8, 3, 8, null, null, 0, null, 0, 4, 9, 1, 2, null, 4, 4, 0, 4, 3, 5, 5, 7, 4, 1, 6, null, 1, 0, null, null, null, 2, 8, 7, 7, null, null, 0, 2, 5, 5, 9, 3, 3, null, 7, 6, 6, 7, 9, 8, 1, 7, 7, 7, 2, 6, null, 7, null, 4, 6, 4, 6, null, null, 9, 1, null, null, null, 5, 5, 5, 4, 2, 2, 8, 5, 1, 1, 3, 1, 3, 7, null, 2, null, 9, 1, 4, 4, 7, 7, null, 1, 5, 6, 2, 7, 3, null, 9, 1, null, 2, 4, 4, 8, null, null, 7, null, 6, null, 7, 4, 3, 5, 8, 4, 8, 5, null, null, 8, null, null, null, 4, 4, null, null, null, null, 8, 3, 5, 5, null, null, null, 1, 2, 0, null, null, 9, 3, null, 8, 3, 7, 1, 8, 9, 0, 1, 8, 2, null, 4, null, null, 8, null, null, null, null, 2, null, 4, 8, 5, 5, 3, 1, null, null, 6, null, 1, null, null, 6, null, null, null, null, 7, 3, null, null, null, 8, 6, 4, null, 6, 9, 0, 7, 8, null, null, 0, 6, 7, null, null, 0, 0, 7, 2, 3, 2, null, 0, 2, 3, null, 0, 1, 7, 9, 0, 7, null, null, null, null, 5, 8, 2, 6, 3, 2, 0, 4, null, null, 0, 9, 1, 1, 1, null, 1, 3, null, 7, 9, 1, 3, 3, 8, null, null, null, null, 6, null, null, null, null, 9, 8, 1, 3, 8, 3, 0, 6, null, null, 8, 5, 6, 5, 2, 1, null, 5, null, 7, 0, 0, null, 9, 3, 9, null, 3, 0, 0, 9, 1, 7, 0, 2, null, 6, 8, 5, null, null, null, null, null, 7, null, 2, 5, null, null, 9, null, null, null, null, null, null, null, null, null, null, null, 4, 1, null, 3, 6, 6, 2, 5, 5, 9, null, null, 7, 8, null, null, 2, 7, 3, 7, 2, 5, null, 1, 3, 4, null, null, 8, 3, 6, 9, null, 1, null, null, null, null, 9, 7, 5, 2, null, 5, null, 6, 4, 5, null, 1, 2, 0, 6, null, 1, 6, null, null, 5, null, 7, 8, 4, 7, 8, 6, 4, null, 5, 6, 7, 9, 1, 0, 4, null, null, null, 6, 4, 8, 4, 5, null, 0, 4, 4, 0, 1, 7, 1, null, 1, null, 3, 6, null, null, null, null, 8, null, 5, 0, 7, 5, null, null, 5, 8, null, null, 3, null, null, 8, null, 2, 4, null, null, null, null, null, null, null, 9, null, 9, null, 9, null, null, null, null, 7, 1, null, null, 2, null, null, 5, 5, 5, 5, 6, 4, null, null, 1, 6, 4, 0, null, 0, 6, 3, 0, null, 5, 5, null, null, null, null, 2, null, 3, 6, null, 3, 0, 5, 0, 1, 0, 3, 4, 9, 9, 2, 7, 3, 8, 6, 9, null, 5, 8, null, null, null, null, 9, 8, 0, 7, null, null, 8, 8, 6, 6, 0, 2, 7, 4, 2, 3, 8, 6, 4, null, 8, null, null, null, 2, 0, null, 1, 3, 5, 4, 2, 2, 5, 8, 8, null, 3, 0, null, 1, 6, 0, null, null, 9, null, 2, null, 6, 8, 2, null, null, 5, null, null, null, 9, 6, 6, 4, 2, 0, null, null, 1, null, 0, null, null, null, 6, 6, null, null, null, 4, 7, 9, null, 0, 1, null, null, 9, null, null, null, 4, null, 8, null, null, null, null, null, null, 4, null, 6, null, 3, null, null, 5, 1, 2, 5, null, 0, 7, 8, null, 7, null, null, 4, null, 4, 4, null, 2, null, 6, null, null, null, 7, null, null, null, null, 6, 4, null, 6, null, 6, 9, null, null, null, 9, 6, null, 9, null, 3, null, 2, null, 7, 7, null, null, 0, null, 6, 3, null, null, null, null, null, null, 1, null, null, null, 6, 9, 7, null, 7, null, 9, 3, 3, null, null, null, null, 4, null, null, 3, null, null, null, 3, 9, null, 0, 3, 1, 9, 6, 7, 9, 4, 8, null, null, 6, null, 1, 3, 7, null, null, null, 3, null, 2, null, 8, 1, 1, null, null, 6, null, 7, 3, 5, null, 6, 3, 4, null, null, 5, 7, 1, null, null, 6, 4, 6, null, null, null, null, 5, 7, 0, 7, 0, null, 5, 8, 5, 5, 4, 5, null, null, null, null, null, null, 1, 7, null, null, 7, null, 9, 9, 6, 4, null, null, 3, 2, 1, null, 0, null, 0, 6, null, null, null, 1, 5, null, null, null, 8, null, null, null, null, 3, 4, 8, null, null, 9, 6, 4, null, null, null, null, 8, 9, null, 1, null, null, null, 7, null, null, null, null, null, 9, null, null, null, 4, 1, 6, 7, 0, null, null, null, 7, null, null, 8, null, null, null, null, null, null, null, 4, null, 9, null, null, null, null, 3, 0, 6, null, 5, null, 9, 9, null, null, 4, 3, 4, null, null, null, null, 8, null, 5, null, null, null, null, 5, 2, null, null, null, null, null, null, null, 2, null, null, 2, 1, 8, 5, null, 0, null, 0, 3, 2, 4, 5, null, null, null, null, null, 7, null, null, 0, null, 0, null, null, null, 0, 3, 9, null, null, null, null, 5, null, null, 0, 5, 0, 0, null, 9, null, null, null, null, null, null, null, null, 8, null, 9, 3, 5, 9, 0, 5, 9, null, null, 9, 4, null, 0, 2, 0, null, null, 7, null, 7, null, 5, 7, 8, 7, null, null, null, 3, 0, 3, null, null, null, null, null, 4, 5, null, null, 2, 3, null, 2, null, null, 7, null, null, 9, null, null, 9, 7, 1, null, null, 1, 6, 1, 8, null, null, 5, null, null, 3, 7, 9, 6, null, null, null, null, 1, null, null, null, 3, 7, 3, 2, 3, 3, null, 1, null, null, null, 1, null, null, 4, 3, 4, 8, 7, null, 0, 3, 0, null, 1, 1, null, null, null, null, null, 5, null, 6, 0, null, 3, 1, null, 6, null, null, 4, 0, 1, null, 6, 1, null, null, 9, 6, 4, 9, 0, 8, 9, 3, 3, 6, null, null, null, null, null, null, null, null, null, null, null, null, 2, null, null, null, null, null, 8, 5, 8, 3, 5, 4, null, 6, null, 0, null, null, 6, null, 4, 3, null, null, null, null, null, null, null, null, null, null, null, null, null, null, 7, 3, null, null, 1, null, 2, 4, null, null, null, 6, null, null, null, 6, null, 5, null, null, null, null, 1, null, null, 3, null, 1, null, 7, 1, null, null, 7, 1, 3, 4, 8, null, null, null, null, null, 4, null, null, 4, null, null, null, 7, null, 6, null, null, 1, null, null, null, 7, 3, 3, null, null, null, null, 3, 0, null, null, 4, null, null, null, null, null, null, null, null, null, null, 8, null, null, 9, null, null, 6, 6, 5, 2, null, 8, 3, 8, null, null, null, null, 6, 7, 0, null, null, null, null, 1, 1, 5, null, 0, 5, null, 5, null, null, null, 1, 2, null, 2, 9, 1, null, 2, 4, 1, null, null, null, 1, 8, 4, 4, 5, 2, null, null, 6, 4, 7, 5, 2, 9, null, 4, null, null, null, null, null, 3, null, null, 5, 9, null, null, null, null, 9, null, 9, null, null, null, 2, null, 1, 9, null, null, null, null, null, 1, 9, 3, null, null, 1, 9, null, 5, 2, 1, 0, null, null, 1, 9, 8, 4, 7, null, null, 5, 7, null, null, null, null, 1, 2, 8, null, 6, 0, null, null, null, null, 0, null, null, null, 6, null, 2, 3, 0, 9, null, null, 1, 4, 6, null, 8, null, null, 5, null, 3, 0, null, 6, null, null, null, null, null, 2, null, null, null, null, null, null, 2, 5, 8, 6, 9, null, null, null, 8, null, null, 9, 6, null, null, null, null, 3, null, null, null, null, 9, null, null, 2, null, null, null, null, null, null, 8, 8, null, null, null, null, null, 9, null, 6, null, 2, 5, null, null, 1, 2, null, 4, null, null, 4, null, null, 3, 5, null, 3, 3, null, null, 1, null, null, null, null, 4, null, 2, 3, null, 4, 5, 3, null, 7, null, null, null, 7, 6, null, null, 1, 3, null, 4, 9, 8, null, null, 0, null, 3, 4, null, 8, null, 1, null, null, 2, 2, null, null, 4, null, null, null, 3, null, null, 2, null, null, null, 4, null, 5, null, null, null, null, 2, null, 5, null, null, null, null, null, null, 2, 7, 5, null, 6, null, null, null, null, 2, null, 0, null, 3, null, 1, null, 9, 4, null, 3, null, null, null, null, null, null, null, 5, 5, 7, null, null, 1, null, 4, 6, null, null, null, 2, null, 5, 9, 0, 6, 2, null, null, null, null, null, null, null, null, null, null, null, null, 5, null, 7, null, 2, 9, null, null, 1, null, null, null, 1, 6, null, 6, null, null, 0, 8, null, 4, null, null, null, null, 4, null, null, 0, null, 6, 0, null, null, null, 4, null, null, null, null, null, 0, null, null, null, null, null, null, null, null, null, null, null, null, 0, 5, 4, 2, 6, 4, 5, 3, 4, null, null, 5, null, null, null, null, 4, null, null, 3, 6, 2, 0, null, 6, 6, null, null, null, null, 0, 6, null, null, null, 3, 9, 4, null, null, null, null, null, 0, null, null, 6, 7, 0, null, 9, 2, null, 3, 3, null, null, 8, null, 3, null, null, null, 8, 5, 3, null, 2, 4, null, 9, 6, 9, null, null, null, null, 6, null, 6, null, 5, 3, null, null, null, null, 4, null, null, null, 9, 0, 9, 7, 1, 1, null, 1, null, 1, 6, null, 5, null, 6, null, null, 1, null, null, null, null, null, null, 5, null, null, null, null, null, 3, null, 6, 1, null, 0, 2, null, null, 0, null, null, 0, null, null, null, null, null, 3, null, null, 8, null, null, 5, 3, 3, null, null, null, null, null, null, null, 3, null, null, 0, 8, 7, null, null, 8, 1, null, null, null, null, null, null, 7, null, null, null, null, null, null, null, null, null, null, null, 5, 2, null, 2, 6, null, null, null, null, null, null, null, 1, 5, 0, null, null, 2, null, 7, null, null, 6, null, null, null, null, null, null, null, null, null, null, null, null, null, 8, null, null, null, null, 3, null, null, 4, null, null, 2, null, null, null, null, 0, 3, null, null, null, null, null, 7, null, 8, null, null, null, null, 8, 5, null, 3, 4, null, null, null, 8, null, null, null, null, null, null, null, null, null, 3, 7, null, null, null, 4, 0, 3, null, null, 6, null, null, null, null, null, null, null, null, null, null, null, null, 8, null, null, null, null, null, 2, null, null, null, null, null, null, null, null, null, 0, null, null, null, 2, null, null, null, 8, 2, null, null, null, null, null, null, null, 8, null, null, null, null, null, null, null, null, null, null, 2, null, null, null, 2, 5, null, null, null, null, null, null, null, null, null, null, null, 2, null, null, null, null, null, 8, null, null, null, null, null, null, null, null, null, null, 0, 5));
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assertEquals(2, solution1.longestUnivaluePath(root));
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}
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}

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