925. Closest Binary Search Tree Value

Given the root of a binary search tree and an integer target, return the key in the BST that is closest in absolute value to the target. If two keys are equally close, return the smaller one. The input gives a level-order BST array and the target separated by ' | '.

Input: A level-order BST array and the target, separated by ' | '.

Output: Integer — the closest key.

Examples

Input: [8,3,10,1,6,null,14] | 5
Output: 6
Explanation: 6 is the closest key to 5.

Input: [4,2,7,1,3] | 6
Output: 7
Explanation: 7 is nearest to 6.

Input: [5] | 3
Output: 5
Explanation: Only key.

Constraints

• 1<=nodes<=10^4
• valid BST

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