- java.lang.Object
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- g2401_2500.s2415_reverse_odd_levels_of_binary_tree.Solution
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public class Solution extends Object
2415 - Reverse Odd Levels of Binary Tree.
Medium
Given the
rootof a perfect binary tree, reverse the node values at each odd level of the tree.- For example, suppose the node values at level 3 are
[2,1,3,4,7,11,29,18], then it should become[18,29,11,7,4,3,1,2].
Return the root of the reversed tree.
A binary tree is perfect if all parent nodes have two children and all leaves are on the same level.
The level of a node is the number of edges along the path between it and the root node.
Example 1:
Input: root = [2,3,5,8,13,21,34]
Output: [2,5,3,8,13,21,34]
Explanation:
The tree has only one odd level.
The nodes at level 1 are 3, 5 respectively, which are reversed and become 5, 3.
Example 2:
Input: root = [7,13,11]
Output: [7,11,13]
Explanation:
The nodes at level 1 are 13, 11, which are reversed and become 11, 13.
Example 3:
Input: root = [0,1,2,0,0,0,0,1,1,1,1,2,2,2,2]
Output: [0,2,1,0,0,0,0,2,2,2,2,1,1,1,1]
Explanation:
The odd levels have non-zero values.
The nodes at level 1 were 1, 2, and are 2, 1 after the reversal.
The nodes at level 3 were 1, 1, 1, 1, 2, 2, 2, 2, and are 2, 2, 2, 2, 1, 1, 1, 1 after the reversal.
Constraints:
- The number of nodes in the tree is in the range
[1, 214]. -
0 <= Node.val <= 105 rootis a perfect binary tree.
- For example, suppose the node values at level 3 are
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Constructor Summary
Constructors Constructor and Description Solution()
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