# [Solved] 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.

## Question

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`

## Python Solution

```# 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

def find_min(root,level):
global m
if not root: return
if root.left==None and root.right==None:m = min(m,level+1)
find_min(root.left,level+1)
find_min(root.right,level+1)

class Solution:
def minDepth(self, root: TreeNode) -> int:
global m
m = 2**31-1
if root==None:return 0
find_min(root,0)
return m``` ##### Abhishek Sharma

Started my Data Science journey in my 2nd year of college and since then continuously into it because of the magical powers of ML and continuously doing projects in almost every domain of AI like ML, DL, CV, NLP.

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