🚀 Data Structures & Algorithms Journey

Welcome to my DSA repository!

This repository contains my solutions to:

• 📚 Striver's A2Z DSA Sheet
• 💻 LeetCode Problems
• 🔥 Daily LeetCode Challenges
• 🎯 Placement Preparation Questions
• 📈 Topic-wise DSA Practice

The primary goal of this repository is to strengthen problem-solving skills, master Data Structures and Algorithms, and prepare for coding interviews and placement opportunities.

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👨‍💻 About Me

Hi, I'm Mohammad Vasim.

🎓 B.Tech Computer Science Engineering Student

💡 Currently learning and exploring:

• Data Structures & Algorithms
• Web Development
• Artificial Intelligence & Machine Learning
• Software Development

This repository serves as my coding journal where I consistently practice and improve my problem-solving skills.

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📂 Repository Structure

DSA/
│
├── Arrays/
│   ├── #1 : Two Sum.java
│   ├── #53 : Maximum Subarray.java
│   └── #121 : Best Time to Buy and Sell Stock.java
│
├── Strings/
│   ├── #125 : Valid Palindrome.java
│   └── #14 : Longest Common Prefix.java
│
├── Hashing/
│   ├── #242 : Valid Anagram.java
│   └── #49 : Group Anagrams.java
│
├── Linked List/
│   ├── #206 : Reverse Linked List.java
│   └── #141 : Linked List Cycle.java
│
├── Stack/
│   ├── #20 : Valid Parentheses.java
│   └── #155 : Min Stack.java
│
├── Queue/
│   └── #232 : Implement Queue using Stacks.java
│
├── Recursion/
│
├── Backtracking/
│   ├── #46 : Permutations.java
│   └── #78 : Subsets.java
│
├── Binary Search/
│   ├── #704 : Binary Search.java
│   ├── #35 : Search Insert Position.java
│   └── #33 : Search in Rotated Sorted Array.java
│
├── Sliding Window/
│
├── Two Pointers/
│
├── Trees/
│   
├── Binary Search Trees/
│
├── Heap/
│
├── Greedy/
│
├── Graph/
│
├── Dynamic Programming/
│   
├── Bit Manipulation/
│
├── Tries/
│
└── README.md

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📚 Topics Covered

Basic Data Structures

• Arrays
• Strings
• Hashing
• Linked List
• Stack
• Queue

Searching & Sorting

• Binary Search
• Sorting Algorithms
• Searching Techniques

Recursion & Backtracking

• Recursion Basics
• Backtracking Problems
• Divide and Conquer

Advanced Problem Solving

• Sliding Window
• Two Pointers
• Greedy Algorithms
• Bit Manipulation

Trees

• Binary Tree
• Binary Search Tree
• Tree Traversals
• Lowest Common Ancestor
• Tree Views
• Tree Construction

Graphs

• BFS
• DFS
• Topological Sort
• Shortest Path Algorithms
• Minimum Spanning Tree
• Disjoint Set Union
• Graph Traversals

Dynamic Programming

• DP Basics
• Memoization
• Tabulation
• 1D DP
• 2D DP
• DP on Trees
• DP on Subsequences

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📌 Striver A2Z DSA Sheet

This repository follows the popular Striver A2Z DSA Sheet.

The sheet covers:

• Programming Fundamentals
• Data Structures
• Algorithms
• Interview Problems
• Coding Patterns
• Competitive Programming Concepts

Each solved problem is organized topic-wise for easy revision and interview preparation.

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💻 LeetCode Solutions

The repository contains solutions to LeetCode problems categorized by topic and difficulty level.

Every solution includes:

• Problem Number
• Problem Name
• Optimized Approach
• Time Complexity
• Space Complexity
• Clean and Readable Code

Example

/*
Problem: Two Sum

Approach:
Use HashMap to store visited elements.

Time Complexity: O(n)
Space Complexity: O(n)
*/

class Solution {
    public int[] twoSum(int[] nums, int target) {

    }
}

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🔥 Daily LeetCode Challenge

Daily LeetCode problems are not stored separately.

Each Daily Challenge is placed inside its respective topic folder to maintain a clean and organized repository structure.

Examples:

Arrays/
├── 1_Two_Sum.java
├── 53_Maximum_Subarray.java
└── 121_Best_Time_To_Buy_And_Sell_Stock.java

Graphs/
├── 200_Number_Of_Islands.java
├── 994_Rotting_Oranges.java
└── 207_Course_Schedule.java

Trees/
├── 100_Same_Tree.java
├── 104_Maximum_Depth_Of_Binary_Tree.java
└── 102_Binary_Tree_Level_Order_Traversal.java

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📝 Solution Naming Convention

Each solution is named using the following format:

#ProblemNumber : Problem Name

Examples:

#1 : Two Sum.java

#121 : Best Time to Buy and Sell Stock.java

#206 : Reverse Linked List.java

#102 : Binary Tree Level Order Traversal.java

#704 : Binary Search.java

#994 : Rotting Oranges.java

For Topic-wise Questions:

Arrays/
│
├── #1 : Two Sum.java
├── #121 : Best Time to Buy and Sell Stock.java
├── #53 : Maximum Subarray.java
└── ...

Linked List/
│
├── #206 : Reverse Linked List.java
├── #141 : Linked List Cycle.java
└── ...

Binary Search/
│
├── #704 : Binary Search.java
├── #33 : Search in Rotated Sorted Array.java
└── ...

📊 Progress Tracker

Category	Progress
Arrays	✅
Strings	✅
Linked List	✅
Sliding Window	✅
Stack	✅
Queue	✅
Binary Search	✅
Recursion	✅
Trees	✅
Graphs	✅
Dynamic Programming	⏳
Greedy	⏳
Heap	⏳

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🎯 Current Goals

• Complete Striver A2Z Sheet
• Solve 500+ LeetCode Problems
• Strengthen DSA Fundamentals
• Improve Problem-Solving Skills
• Master Dynamic Programming
• Become Interview Ready
• Prepare for Product-Based Companies

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🚀 Languages Used

• Java ☕ Currently focusing on Java for Data Structures and Algorithms.

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📖 Resources Used

Striver A2Z DSA Sheet

https://takeuforward.org

LeetCode

https://leetcode.com

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🏆 Why This Repository?

This repository helps me:

• Track my coding journey
• Maintain consistency
• Revise important concepts
• Prepare for coding interviews
• Build strong problem-solving skills

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⭐ Support

If you find this repository useful, consider giving it a ⭐.

It motivates me to keep learning, solving, and sharing.

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Repository Description

A comprehensive collection of Data Structures and Algorithms solutions including Striver A2Z Sheet, LeetCode Problems, Daily LeetCode Challenges, and topic-wise interview preparation questions implemented primarily in Java.