Maximum Depth of Binary Tree – Leetcode Solution

In this post, we are going to solve the 104. Maximum Depth of Binary Tree problem of Leetcode. This problem 104. Maximum Depth of Binary Tree is a Leetcode easy level problem. Let’s see the code, 104. Maximum Depth of Binary Tree – Leetcode Solution.

Problem

Given the `root` of a binary tree, return its maximum depth.

A binary tree’s maximum depth is the number of nodes along the longest path from the root node down to the farthest leaf node.

Example 1 :

``````Input: root = [3,9,20,null,null,15,7]
Output: 3``````

Example 2 :

``````Input: root = [1,null,2]
Output: 2``````

Constraints

• The number of nodes in the tree is in the range `[0, 104]`.
• `-100 <= Node.val <= 100`

Now, let’s see the code of 104. Maximum Depth of Binary Tree – Leetcode Solution.

Maximum Depth of Binary Tree – Leetcode Solution

104. Maximum Depth of Binary Tree – Solution in Java

```/**
* Definition for a binary tree node.
* public class TreeNode {
*     int val;
*     TreeNode left;
*     TreeNode right;
*     TreeNode() {}
*     TreeNode(int val) { this.val = val; }
*     TreeNode(int val, TreeNode left, TreeNode right) {
*         this.val = val;
*         this.left = left;
*         this.right = right;
*     }
* }
*/
class Solution {
public int maxDepth(TreeNode root) {
if(root == null) return 0;
int leftDepth = maxDepth(root.left);
int rightDepth = maxDepth(root.right);
return Math.max(leftDepth,rightDepth) + 1;
}
}```

104. Maximum Depth of Binary Tree – Solution in C++

```/**
* Definition for a binary tree node.
* struct TreeNode {
*     int val;
*     TreeNode *left;
*     TreeNode *right;
*     TreeNode() : val(0), left(nullptr), right(nullptr) {}
*     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
*     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
* };
*/
class Solution {
public:
int maxDepth(TreeNode* root) {
if(!root) return 0;
int maxLeft = maxDepth(root->left);
int maxRight = maxDepth(root->right);
return max(maxLeft, maxRight)+1;
}
};```

104. Maximum Depth of Binary Tree– Solution in Python

```# Definition for a binary tree node.
# class TreeNode:
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution:
def maxDepth(self, root: Optional[TreeNode]) -> int:
def dfs(root, depth):
if not root: return depth
return max(dfs(root.left, depth + 1), dfs(root.right, depth + 1))

return dfs(root, 0)
```

Note: This problem 104. Maximum Depth of Binary Tree is generated by Leetcode but the solution is provided by CodingBroz. This tutorial is only for Educational and Learning purpose.