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.<p>Medium</p> <p>Given the <code>root</code> of a binary tree, flatten the tree into a &ldquo;linked list&rdquo;:</p> <ul> <li>The &ldquo;linked list&rdquo; should use the same <code>TreeNode</code> class where the <code>right</code> child pointer points to the next node in the list and the <code>left</code> child pointer is always <code>null</code>.</li> <li>The &ldquo;linked list&rdquo; should be in the same order as a <a href="https://en.wikipedia.org/wiki/Tree_traversal#Pre-order,_NLR" target="_top"><strong>pre-order</strong> <strong>traversal</strong></a> of the binary tree.</li> </ul> <p><strong>Example 1:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2021/01/14/flaten.jpg" alt="" /></p> <p><strong>Input:</strong> root = [1,2,5,3,4,null,6]</p> <p><strong>Output:</strong> [1,null,2,null,3,null,4,null,5,null,6]</p> <p><strong>Example 2:</strong></p> <p><strong>Input:</strong> root = []</p> <p><strong>Output:</strong> []</p> <p><strong>Example 3:</strong></p> <p><strong>Input:</strong> root = [0]</p> <p><strong>Output:</strong> [0]</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the tree is in the range <code>[0, 2000]</code>.</li> <li><code>-100 <= Node.val <= 100</code></li> </ul> <p><strong>Follow up:</strong> Can you flatten the tree in-place (with <code>O(1)</code> extra space)?</p>

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
void	flatten(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

flatten

public void flatten(TreeNode root)