# LeetCode Study Tracker Example


# LeetCode Study Tracker

| #   | Title                                          | Difficulty | Category               | Solved Date | Notes/Approach                         | Status |
| --- | ---------------------------------------------- | ---------- | ---------------------- | ----------- | -------------------------------------- | ------ |
| 1   | Two Sum                                        | Easy       | Arrays                 | YYYY-MM-DD  | Used hash map for O(n) solution        | ✅      |
| 55  | Jump Game                                      | Medium     | Greedy/DP              | YYYY-MM-DD  | Greedy: Track farthest index           | ✅      |
| 121 | Best Time to Buy and Sell Stock                | Easy       | Arrays/Greedy          | YYYY-MM-DD  | Track min price, max profit            | ✅      |
| 322 | Coin Change                                    | Medium     | Dynamic Programming    | YYYY-MM-DD  | DP: Bottom-up approach                 | ❌      |
| 53  | Maximum Subarray                               | Easy       | Dynamic Programming    | YYYY-MM-DD  | Used Kadane&#39;s Algorithm                | ✅      |
| 200 | Number of Islands                              | Medium     | Graph/DFS              | YYYY-MM-DD  | Used DFS to count connected components | ✅      |
| 3   | Longest Substring Without Repeating Characters | Medium     | Strings/Sliding Window | YYYY-MM-DD  | Two-pointer sliding window technique   | ✅      |
| 70  | Climbing Stairs                                | Easy       | Dynamic Programming    | YYYY-MM-DD  | Fibonacci DP approach                  | ✅      |

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### Legend:
- **#**: Question number on LeetCode.
- **Title**: Name of the problem.
- **Difficulty**: Easy, Medium, or Hard.
- **Category**: Relevant data structures/algorithm used.
- **Solved Date**: The date you solved or studied the question.
- **Notes/Approach**: Explanation of how you solved it or notes for future reference.
- **Status**: 
  - ✅ = Solved
  - ❌ = Still working on it


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> 作者: Daniel Lau  
> URL: https://daniel-and-lily.us/posts/leetcode/c6fa81c/  

