| 💻 Question Name | 🎯 Pattern | 🧠 Difficulty | 🔗 Practice Link |
|---|---|---|---|
| Two Sum | Hashing, Two-pointer | Easy | LeetCode #1 |
| Remove Duplicates from Sorted Array | Two-pointer | Easy | LeetCode #26 |
| Best Time to Buy and Sell Stock | Sliding Window | Easy | LeetCode #121 |
| 3Sum | Two-pointer, Sorting | Medium | LeetCode #15 |
| Container With Most Water | Two-pointer | Medium | LeetCode #11 |
| Subarray Sum Equals K | Prefix Sum, HashMap | Medium | LeetCode #560 |
| Product of Array Except Self | Prefix & Suffix Product | Medium | LeetCode #238 |
| Maximum Subarray Sum After One Deletion | Dynamic Programming (Kadane Var.) | Hard | LeetCode #1186 |
| Merge Intervals | Sorting, Merging | Hard | LeetCode #56 |
| Median of Two Sorted Arrays | Binary Search on Partition | Hard | LeetCode #4 |
| 💻 Question Name | 🎯 Pattern / Concept | 🧠 Difficulty | 🔗 Practice Link |
|---|---|---|---|
| Valid Anagram | Frequency Count (HashMap) | Easy | LeetCode #242 |
| Implement strStr() (Substring Search) | Two-pointer / Brute Force | Easy | LeetCode #28 |
| Longest Common Prefix | Vertical Scanning / Sorting | Easy | LeetCode #14 |
| Group Anagrams | HashMap + Sorting | Medium | LeetCode #49 |
| Longest Palindromic Substring | Expand Around Center / DP | Medium | LeetCode #5 |
| Longest Substring Without Repeating Characters | Sliding Window + HashSet | Medium | LeetCode #3 |
| Multiply Strings | Simulated Multiplication (Manual) | Medium | LeetCode #43 |
| Minimum Window Substring | Sliding Window + Frequency Map | Hard | LeetCode #76 |
| Wildcard Matching | DP + Greedy Edge Cases | Hard | LeetCode #44 |
| Word Break | DP + HashSet | Hard | LeetCode #139 |
| 💻 Question Name | 🎯 Pattern / Concept | 🧠 Difficulty | 🔗 Practice Link |
|---|---|---|---|
| Reverse a Linked List | Iterative / Recursion | Easy | LeetCode #206 |
| Merge Two Sorted Linked Lists | Two-pointer / Recursion | Easy | LeetCode #21 |
| Detect Cycle in Linked List | Floyd’s Cycle Detection (Tortoise-Hare) | Medium | LeetCode #141 |
| Remove Nth Node From End | Two-pointer | Medium | LeetCode #19 |
| Intersection of Two Linked Lists | Two-pointer / Length equalization | Easy | LeetCode #160 |
| Palindrome Linked List | Reverse second half & compare | Medium | LeetCode #234 |
| Add Two Numbers | Simulated addition with carry | Medium | LeetCode #2 |