🎋 Day 22

Author: AkashRajpurohit

README.md

@@ -37,7 +37,7 @@
 
 ## Week 4 🚧
 
-Coming Soon...
+1. [Minimum Depth of Binary Tree](https://leetcode.com/explore/challenge/card/october-leetcoding-challenge/562/week-4-october-22nd-october-28th/3504/) ➡️ [CPP Solution](Week4/minDepth.cpp)
 
 ## Week 5 🚧
 

Week4/minDepth.cpp

@@ -0,0 +1,43 @@
+/**
+ * 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 minDepth(TreeNode* root) {
+        if(root == NULL) return 0;
+        queue<TreeNode*> q;
+        
+        q.push(root);
+        int level = 1;
+        
+        while(!q.empty()) {
+            int n = q.size();
+            
+            while(n--) {
+                TreeNode* current = q.front();
+                q.pop();
+                
+                if(current->left == NULL && current->right == NULL)
+                    return level;
+                
+                if(current->left)
+                    q.push(current->left);
+                
+                if(current->right)
+                    q.push(current->right);
+            }
+            
+            level++;
+        }
+        
+        return level;
+    }
+};