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MD ARIFUL HAQUE

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1325. Delete Leaves With a Given Value

1325. Delete Leaves With a Given Value

Medium

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`

Solution:

``````/**
* Definition for a binary tree node.
* class TreeNode {
*     public \$val = null;
*     public \$left = null;
*     public \$right = null;
*     function __construct(\$val = 0, \$left = null, \$right = null) {
*         \$this->val = \$val;
*         \$this->left = \$left;
*         \$this->right = \$right;
*     }
* }
*/
class Solution {

/**
* @param TreeNode \$root
* @param Integer \$target
* @return TreeNode
*/
function removeLeafNodes(\$root, \$target) {
if (\$root == null) return null;

if (\$root->left == null && \$root->right == null && \$root->val == \$target)
return null;

\$root->left = \$this->removeLeafNodes(\$root->left, \$target);
\$root->right = \$this->removeLeafNodes(\$root->right, \$target);

if (\$root->left == null && \$root->right == null && \$root->val == \$target)
return null;

return \$root;
}
}
``````