Package g0101_0200.s0114_flatten_binary_tree_to_linked_list

Class Solution

java.lang.Object
g0101_0200.s0114_flatten_binary_tree_to_linked_list.Solution
public class Solution extends Object
114 - Flatten Binary Tree to Linked List.

Medium

Given the root of a binary tree, flatten the tree into a “linked list”:

  • The “linked list” should use the same TreeNode class where the right child pointer points to the next node in the list and the left child pointer is always null.
  • The “linked list” should be in the same order as a pre-order traversal of the binary tree.

Example 1:

Input: root = [1,2,5,3,4,null,6]

Output: [1,null,2,null,3,null,4,null,5,null,6]

Example 2:

Input: root = []

Output: []

Example 3:

Input: root = [0]

Output: [0]

Constraints:

  • The number of nodes in the tree is in the range [0, 2000].
  • -100 <= Node.val <= 100

Follow up: Can you flatten the tree in-place (with O(1) extra space)?

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • flatten

      public void flatten(TreeNode root)