1325. Delete Leaves With a Given Value ¶
Problem
Given a binary tree root
and an integer target
, delete all the leaf nodes with value target
.
Note that once you delete a leaf node with value target
, if its parent node becomes a leaf node and has the value target
, it should also be deleted (you need to continue doing that until you cannot).
Example 1:
Input: root = [1,2,3,2,null,2,4], target = 2 Output: [1,null,3,null,4] Explanation: Leaf nodes in green with value (target = 2) are removed (Picture in left). After removing, new nodes become leaf nodes with value (target = 2) (Picture in center).
Example 2:
Input: root = [1,3,3,3,2], target = 3 Output: [1,3,null,null,2]
Example 3:
Input: root = [1,2,null,2,null,2], target = 2 Output: [1] Explanation: Leaf nodes in green with value (target = 2) are removed at each step.
Constraints:
- The number of nodes in the tree is in the range
[1, 3000]
. 1 <= Node.val, target <= 1000