Search In A Binary Search Tree Problem
Description
LeetCode Problem 700.
You are given the root of a binary search tree (BST) and an integer val.
Find the node in the BST that the node’s value equals val and return the subtree rooted with that node. If such a node does not exist, return null.
Example 1:
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Input: root = [4,2,7,1,3], val = 2
Output: [2,1,3]
Example 2:
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Input: root = [4,2,7,1,3], val = 5
Output: []
Constraints:
- The number of nodes in the tree is in the range [1, 5000].
- 1 <= Node.val <= 10^7
- root is a binary search tree.
- 1 <= val <= 10^7
Sample C++ Code
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/**
* Definition for a binary tree node.
* struct TreeNode {
* int val;
* TreeNode *left;
* TreeNode *right;
* TreeNode() : val(0), left(nullptr), right(nullptr) {}
* TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
* TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
* };
*/
class Solution {
public:
TreeNode* searchBST(TreeNode* root, int val) {
if (root == NULL)
return NULL;
if (root->val == val)
return root;
else if (root->val > val)
return searchBST(root->left, val);
else
return searchBST(root->right, val);
}
};