Minimum Depth of Binary Tree Leetcode Solution

In this post, we are going to solve the Minimum Depth of Binary Tree Leetcode Solution problem of Leetcode. This Leetcode problem is done in many programming languages like C++, Java, and Python.

Table of Contents

Problem

Given a binary tree, find its minimum depth.

The minimum depth is the number of nodes along the shortest path from the root node down to the nearest leaf node.

Note: A leaf is a node with no children.

Example 1:

Input: root = [3,9,20,null,null,15,7]
Output: 2

Example 2:

Input: root = [2,null,3,null,4,null,5,null,6]
Output: 5

Constraints:

The number of nodes in the tree is in the range [0, 10⁵].
-1000 <= Node.val <= 1000

Now, let’s see the leetcode solution of Minimum Depth of Binary Tree Leetcode Solution.

Minimum Depth of Binary Tree Leetcode Solution in Python

class Solution:
  def minDepth(self, root: Optional[TreeNode]) -> int:
    if not root:
      return 0
    if not root.left:
      return self.minDepth(root.right) + 1
    if not root.right:
      return self.minDepth(root.left) + 1
    return min(self.minDepth(root.left), self.minDepth(root.right)) + 1

Minimum Depth of Binary Tree Leetcode Solution in CPP

class Solution {
 public:
  int minDepth(TreeNode* root) {
    if (root == nullptr)
      return 0;
    if (root->left == nullptr)
      return minDepth(root->right) + 1;
    if (root->right == nullptr)
      return minDepth(root->left) + 1;
    return min(minDepth(root->left), minDepth(root->right)) + 1;
  }
};

Minimum Depth of Binary Tree Leetcode Solution in Java

class Solution {
  public int minDepth(TreeNode root) {
    if (root == null)
      return 0;
    if (root.left == null)
      return minDepth(root.right) + 1;
    if (root.right == null)
      return minDepth(root.left) + 1;
    return Math.min(minDepth(root.left), minDepth(root.right)) + 1;
  }
}

Note: This problem Minimum Depth of Binary Tree is generated by Leetcode but the solution is provided by Chase2learn This tutorial is only for Educational and Learning purposes.