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 it’s parent node becomes a leaf node and has the value `target`, it should also be deleted (you need to continue doing that until you can’t).

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: 
Explanation: Leaf nodes in green with value (target = 2) are removed at each step.
```

Example 4:

```Input: root = [1,1,1], target = 1
Output: []
```

Example 5:

```Input: root = [1,2,3], target = 1
Output: [1,2,3]
```

Constraints:

• `1 <= target <= 1000`
• The given binary tree will have between `1` and `3000` nodes.
• Each node’s value is between `[1, 1000]`.

Solution:

``````/**
* Definition for a binary tree node.
* function TreeNode(val, left, right) {
*     this.val = (val===undefined ? 0 : val)
*     this.left = (left===undefined ? null : left)
*     this.right = (right===undefined ? null : right)
* }
*/
/**
* @param {TreeNode} root
* @param {number} target
* @return {TreeNode}
*/
var removeLeafNodes = function(root, target) {
if (root === null) return null;
root.left = removeLeafNodes(root.left, target);
root.right = removeLeafNodes(root.right, target);
// return null to remove that leaf
if (root.val === target && root.left === null && root.right === null) {
return null;
}
return root;
};``````