129_Sum_Root_to_Leaf_Numbers

Leetcode 129: Sum Root to Leaf Numbers
--------------------------------------
Detailed Explanation can be found here: https://youtu.be/tanL9EJVfrU

C++:
----
class Solution {
public:
    int sumNumbers(TreeNode* root) {
        if(!root) return 0;
        int result = 0;
        findsum(root, 0, result);
        return result;
    }
    void findsum(TreeNode* root, int val, int& result) {
        int curr = val*10 + root->val;
        if(!root->left && !root->right){
            result += curr;
            return;
        }
        if(root->left) findsum(root->left, curr, result);
        if(root->right) findsum(root->right, curr, result);
    }
};

Java:
-----
class Solution {
    private int result;
    private void findsum(TreeNode root, int val) {
        int curr = val*10 + root.val;
        if(root.left == null && root.right == null){
            result += curr;
            return;
        }
        if(root.left != null) findsum(root.left, curr);
        if(root.right != null) findsum(root.right, curr);
    }
    
    public int sumNumbers(TreeNode root) {
        if(root == null) return 0;
        result = 0;
        findsum(root, 0);
        return result;
    }
}

Python3:
--------
class Solution:
    def sumNumbers(self, root: TreeNode) -> int:
        if root == None: return 0
        self.result = 0
        self.findsum(root, 0)
        return self.result
    
    def findsum(self, root, val):
        curr = val*10 + root.val
        if root.left == None and root.right == None:
            self.result += curr
            return
        
        if root.left != None: self.findsum(root.left, curr)
        if root.right != None: self.findsum(root.right, curr)
  
  
****** Please Subscribe Knowledge Center: http://youtube.com/c/KnowledgeCenter ********