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 java.lang.Object
2641 - Cousins in Binary Tree II.

Medium

Given the root of a binary tree, replace the value of each node in the tree with the sum of all its cousins’ values.

Two nodes of a binary tree are cousins if they have the same depth with different parents.

Return the root of the modified tree.

Note that the depth of a node is the number of edges in the path from the root node to it.

Example 1:

Input: root = [5,4,9,1,10,null,7]

Output: [0,0,0,7,7,null,11]

Explanation: The diagram above shows the initial binary tree and the binary tree after changing the value of each node.

  • Node with value 5 does not have any cousins so its sum is 0.
  • Node with value 4 does not have any cousins so its sum is 0.
  • Node with value 9 does not have any cousins so its sum is 0.
  • Node with value 1 has a cousin with value 7 so its sum is 7.
  • Node with value 10 has a cousin with value 7 so its sum is 7.
  • Node with value 7 has cousins with values 1 and 10 so its sum is 11.

Example 2:

Input: root = [3,1,2]

Output: [0,0,0]

Explanation: The diagram above shows the initial binary tree and the binary tree after changing the value of each node.

  • Node with value 3 does not have any cousins so its sum is 0.
  • Node with value 1 does not have any cousins so its sum is 0.
  • Node with value 2 does not have any cousins so its sum is 0.

Constraints:

  • The number of nodes in the tree is in the range [1, 105].
  • 1 <= Node.val <= 104

  • 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