## Solutions

### Unique Paths III | Backtracking Solution Explained

LeetCode 980. Unique Paths III. We are going to look at the backtracking approach in detail using visuals...

### Surrounded Regions | DFS Solution Explained

LeetCode 130. Surrounded Regions. I solve the problem using DFS approach. This is more of an implementation based...

### 3Sum | LeetCode | Solution Explained

LeetCode 15. 3Sum is a very popular interview question. I explain the brute-force solution, binary search optimization and...

### Count Complete Tree Nodes | Solution (Explained)

LeetCode 222. Count Complete Tree Nodes is a medium problem if you go by the naive solution. To...

### Find Minimum in Rotated Sorted Array II | Solution Explained

What makes LeetCode 154. Find Minimum in Rotated Sorted Array II fun is the optimized solution. I explain...

### Insert Delete GetRandom O(1) | Solution Explained

LeetCode 380. Insert Delete GetRandom O(1) is an implementation based question, requiring us to know the time complexities...

### Next Greater Element I | Solution Explained + Stack Optimization

LeetCode 496. Next Greater Element I is a simple problem, since brute-force solution can get accepted. But, we...

### Path Sum III | Solution Explained

LeetCode 437. Path Sum III. I explain the brute-force solution and the optimized solutions in detail for reducing...

### Best Time to Buy and Sell Stock | A Compilation of Solutions

Best Time to Buy and Sell Stock is a popular series of problems on LeetCode. In this...

### Best Time to Buy and Sell Stock with Cooldown | Solution Explained

LeetCode 309. Best Time to Buy and Sell Stock with Cooldown. I solve this problem using recursion. Solution...