Package g2601_2700.s2641_cousins_in_binary_tree_ii

Class Solution

java.lang.Object

g2601_2700.s2641_cousins_in_binary_tree_ii.Solution

public class Solution
extends Object

2641 - Cousins in Binary Tree II.<p>Medium</p> <p>Given the <code>root</code> of a binary tree, replace the value of each node in the tree with the <strong>sum of all its cousins&rsquo; values</strong>.</p> <p>Two nodes of a binary tree are <strong>cousins</strong> if they have the same depth with different parents.</p> <p>Return <em>the</em> <code>root</code> <em>of the modified tree</em>.</p> <p><strong>Note</strong> that the depth of a node is the number of edges in the path from the root node to it.</p> <p><strong>Example 1:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2023/01/11/example11.png" alt="" /></p> <p><strong>Input:</strong> root = [5,4,9,1,10,null,7]</p> <p><strong>Output:</strong> [0,0,0,7,7,null,11]</p> <p><strong>Explanation:</strong> The diagram above shows the initial binary tree and the binary tree after changing the value of each node.</p> <ul> <li>Node with value 5 does not have any cousins so its sum is 0.</li> <li>Node with value 4 does not have any cousins so its sum is 0.</li> <li>Node with value 9 does not have any cousins so its sum is 0.</li> <li>Node with value 1 has a cousin with value 7 so its sum is 7.</li> <li>Node with value 10 has a cousin with value 7 so its sum is 7.</li> <li>Node with value 7 has cousins with values 1 and 10 so its sum is 11.</li> </ul> <p><strong>Example 2:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2023/01/11/diagram33.png" alt="" /></p> <p><strong>Input:</strong> root = [3,1,2]</p> <p><strong>Output:</strong> [0,0,0]</p> <p><strong>Explanation:</strong> The diagram above shows the initial binary tree and the binary tree after changing the value of each node.</p> <ul> <li>Node with value 3 does not have any cousins so its sum is 0.</li> <li>Node with value 1 does not have any cousins so its sum is 0.</li> <li>Node with value 2 does not have any cousins so its sum is 0.</li> </ul> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the tree is in the range <code>[1, 10⁵]</code>.</li> <li><code>1 <= Node.val <= 10⁴</code></li> </ul>

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
TreeNode	replaceValueInTree(TreeNode root)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Solution

public Solution()

Method Details

replaceValueInTree

public TreeNode replaceValueInTree(TreeNode root)