DSA is really tough, but you don't seem to struggle?🤨

I get this question a lot.

Here are some of the hardest questions you might face in an interview.

Practice these using the 𝟯-𝟳-𝟭𝟱 𝗿𝘂𝗹𝗲:

First solve the question, then note down the answer. After three days, try to remember the question from the answer and solve it again.

Repeat the same after 7 and 15 days.

This way, you'll solve the same question 4 times in 15 days, making it easier if you encounter it again.

𝟭. 𝗔𝗿𝗿𝗮𝘆𝘀 & 𝗦𝘁𝗿𝗶𝗻𝗴𝘀
- Minimum Window Substring
- Trapping Rain Water
- Largest Rectangle in Histogram

𝟮. 𝗟𝗶𝗻𝗸𝗲𝗱 𝗟𝗶𝘀𝘁𝘀
- Merge k Sorted Lists
- Reverse Nodes in k-Group
- LFU Cache

𝟯. 𝗧𝗿𝗲𝗲𝘀
- Binary Tree Maximum Path Sum
- Serialize and Deserialize Binary Tree
- Vertical Order Traversal of a Binary Tree

𝟰. 𝗗𝘆𝗻𝗮𝗺𝗶𝗰 𝗣𝗿𝗼𝗴𝗿𝗮𝗺𝗺𝗶𝗻𝗴
- Edit Distance
- Burst Balloons
- Shortest Common Supersequence

𝟱. 𝗚𝗿𝗮𝗽𝗵𝘀
- Alien Dictionary
- Minimum Cost to Make at Least One Valid Path in a Grid
- Swim in Rising Water

𝟲. 𝗥𝗲𝗰𝘂𝗿𝘀𝗶𝗼𝗻 & 𝗕𝗮𝗰𝗸𝘁𝗿𝗮𝗰𝗸𝗶𝗻𝗴
- N-Queens II
- Sudoku Solver
- Word Search II

𝟳. 𝗦𝗼𝗿𝘁𝗶𝗻𝗴 & 𝗦𝗲𝗮𝗿𝗰𝗵𝗶𝗻𝗴
- Count of Smaller Numbers After Self
- Median of Two Sorted Arrays
- Split Array Largest Sum

𝟴. 𝗗𝗲𝘀𝗶𝗴𝗻
- Design Search Autocomplete System
- Design In-Memory File System
- Design Excel Sum Formula

𝟵. 𝗚𝗿𝗲𝗲𝗱𝘆
- Minimum Number of Arrows to Burst Balloons
- Candy
- Patching Array

𝟭𝟬. 𝗕𝗶𝘁 𝗠𝗮𝗻𝗶𝗽𝘂𝗹𝗮𝘁𝗶𝗼𝗻
- Maximum Product of Word Lengths
- Smallest Sufficient Team
- Minimum Cost to Connect Two Groups of Points

𝟭𝟭. 𝗧𝘄𝗼 𝗣𝗼𝗶𝗻𝘁𝗲𝗿𝘀
- Minimum Window Subsequence
- Minimum Operations to Make a Subsequence
- Minimum Adjacent Swaps to Reach the Kth Smallest Number

𝟭𝟮. 𝗛𝗲𝗮𝗽
- Minimum Number of Refueling Stops
- Sliding Window Median
- Minimum Number of K Consecutive Bit Flips

By following the 3-7-15 rule and practicing these tough questions regularly, you'll build strong problem-solving skills and be well-prepared for your interviews.

Keep pushing yourself, and remember, consistency is key.

Best DSA RESOURCES: https://topmate.io/coding/886874

All the best 👍👍