### LeetCode Challenge #112. Path Sum

Given the `root` of a binary tree and an integer `targetSum`, return `true` if the tree has a root-to-leaf path such that adding up all the values along the path equals `targetSum`.

leaf is a node with no children.

Example 1:

```Input: root = [5,4,8,11,null,13,4,7,2,null,null,null,1], targetSum = 22
Output: true
Explanation: The root-to-leaf path with the target sum is shown.
```

Example 2:

```Input: root = [1,2,3], targetSum = 5
Output: false
Explanation: There two root-to-leaf paths in the tree:
(1 --> 2): The sum is 3.
(1 --> 3): The sum is 4.
There is no root-to-leaf path with sum = 5.
```

Example 3:

```Input: root = [], targetSum = 0
Output: false
Explanation: Since the tree is empty, there are no root-to-leaf paths.
```

Constraints:

• The number of nodes in the tree is in the range `[0, 5000]`.
• `-1000 <= Node.val <= 1000`
• `-1000 <= targetSum <= 1000`
##### Video Solution
###### Java Solution
```				```
class Solution {
public boolean hasPathSum(TreeNode root, int targetSum) {
if(root == null){
return false ;
}
if(root.left == null && root.right == null && root.val == targetSum){
return true ;
}
boolean ans1 = hasPathSum(root.left , targetSum-root.val);
boolean ans2 = hasPathSum(root.right, targetSum-root.val);
return ans1 || ans2 ;
}
}
```
```