g1201_1300.s1261_find_elements_in_a_contaminated_binary_tree

Class FindElements

java.lang.Object

g1201_1300.s1261_find_elements_in_a_contaminated_binary_tree.FindElements

public class FindElements
extends Object

1261 - Find Elements in a Contaminated Binary Tree.

Medium

Given a binary tree with the following rules:

1. root.val == 0
2. If treeNode.val == x and treeNode.left != null, then treeNode.left.val == 2 * x + 1
3. If treeNode.val == x and treeNode.right != null, then treeNode.right.val == 2 * x + 2

Now the binary tree is contaminated, which means all treeNode.val have been changed to -1.

Implement the FindElements class:

• FindElements(TreeNode* root) Initializes the object with a contaminated binary tree and recovers it.
• bool find(int target) Returns true if the target value exists in the recovered binary tree.

Example 1:

Input [“FindElements”,“find”,“find”] [[[-1,null,-1]],[1],[2]]

Output: [null,false,true]

Explanation:

FindElements findElements = new FindElements([-1,null,-1]); 
findElements.find(1); // return False 
findElements.find(2); // return True

Example 2:

Input [“FindElements”,“find”,“find”,“find”] [[[-1,-1,-1,-1,-1]],[1],[3],[5]]

Output: [null,true,true,false]

Explanation:

FindElements findElements = new FindElements([-1,-1,-1,-1,-1]); 
findElements.find(1); // return True 
findElements.find(3); // return True 
findElements.find(5); // return False

Example 3:

Input [“FindElements”,“find”,“find”,“find”,“find”] [[[-1,null,-1,-1,null,-1]],[2],[3],[4],[5]]

Output: [null,true,false,false,true]

Explanation:

FindElements findElements = new FindElements([-1,null,-1,-1,null,-1]); 
findElements.find(2); // return True 
findElements.find(3); // return False 
findElements.find(4); // return False 
findElements.find(5); // return True

Constraints:

• TreeNode.val == -1
• The height of the binary tree is less than or equal to 20
• The total number of nodes is between [1, 104]
• Total calls of find() is between [1, 104]
• 0 <= target <= 106

Constructor Summary

Constructors

Constructor and Description
FindElements(TreeNode root)

Method Summary

Modifier and Type	Method and Description
boolean	find(int target)

Methods inherited from class java.lang.Object

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

Constructor Detail

FindElements

public FindElements(TreeNode root)

Method Detail

find

public boolean find(int target)