Package g0401_0500.s0450_delete_node_in_a_bst

Class Solution

  • public class Solution
extends Object
    450 - Delete Node in a BST.

    Medium

    Given a root node reference of a BST and a key, delete the node with the given key in the BST. Return the root node reference (possibly updated) of the BST.

    Basically, the deletion can be divided into two stages:

    1. Search for a node to remove.
    2. If the node is found, delete the node.

    Example 1:

    Input: root = [5,3,6,2,4,null,7], key = 3

    Output: [5,4,6,2,null,null,7]

    Explanation:

     Given key to delete is 3. So we find the node with value 3 and delete it.
 One valid answer is [5,4,6,2,null,null,7], shown in the above BST.
 Please notice that another valid answer is [5,2,6,null,4,null,7] and it's also accepted.

    Example 2:

    Input: root = [5,3,6,2,4,null,7], key = 0

    Output: [5,3,6,2,4,null,7]

    Explanation: The tree does not contain a node with value = 0.

    Example 3:

    Input: root = [], key = 0

    Output: []

    Constraints:

    • The number of nodes in the tree is in the range [0, 104].
    • -105 <= Node.val <= 105
    • Each node has a unique value.
    • root is a valid binary search tree.
    • -105 <= key <= 105

    Follow up: Could you solve it with time complexity O(height of tree)?

    • Constructor Detail

      • Solution

        public Solution()