This repository contains my solutions to 100 essential LeetCode problems, covering Data Structures and Algorithms commonly asked in FAANG / top product-based company interviews.
The goal of this repo is to:
- Build strong DSA fundamentals
- Practice patterns, not just problems
- Improve problem-solving + coding speed
- Become interview-ready
| Status | Count |
|---|---|
| ✅ Problems Solved | 0 / 100 |
| 🕒 Ongoing | Yes |
| 🎯 Goal | Complete within 100 Days |
I update this repository daily.
This repository is organized by DSA topics to help understand patterns instead of random problem solving.
| Folder Name | Description |
|---|---|
| Array | Problems based on traversal, prefix sums, sorting, searching, etc. |
| String | Pattern matching, frequency maps, transformations, substring logic. |
| LinkedList | Node operations, reversing, merging, cycle detection, etc. |
| Stack | Parenthesis problems, monotonic stack, evaluators, backtracking helper. |
| Queue | FIFO operations, circular queues, and queue-based patterns. |
| Hashing | Problems using hash maps/sets for fast lookup and frequency counts. |
| TwoPointers | Problems involving two indices narrowing or expanding across arrays/strings. |
| BinarySearch | Classic binary search + binary search on answer problems. |
| SlidingWindow | Subarray/substring problems optimizing using dynamic windows. |
| Trees | Binary trees, traversal techniques, recursive DFS, BFS. |
| Graphs | Graph traversal (BFS, DFS), shortest paths, connectivity problems. |
| DynamicProgramming | Optimization problems using memoization/tabulation. |
Each problem goes inside the correct topic folder.
File name format: ProblemName.cpp ProblemName.py ProblemName.java
You may submit solutions in:
- C++
- Python
- Java
Click the Fork button on top-right.
git clone https://github.com/ /100-LeetCode-Problems.git cd 100-LeetCode-Problems
git checkout -b add-solution-problemname
Place your file correctly. Example:
Inside the same folder, add a short explanation: Approach
Explain your logic in 3-6 lines.
Complexity
Time: O(...) Space: O(...)
git add . git commit -m "Added Two Sum solution in C++" git push origin add-solution-problemname
Go to your fork → Compare & pull request → Submit → Done ✅
We will review and merge.
| Rule | Description |
|---|---|
| Write clean code | Make it easy to understand |
| Add comments if needed | Especially for tricky logic |
| Prefer optimized solution | Brute force allowed only with explanation |
| Add time & space complexity | Required |
| No copy-paste answers | Must be your own understanding |
This section will include contributors as PRs are merged.