DSA-Practice

Welcome to my Data Structures and Algorithms (DSA) practice repository!
This repository contains solutions to problems from NeetCode 150 and LeetCode to improve my problem-solving skills.

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📂 Table of Contents (NeetCode 150 Categories)

1. Arrays & Hashing
2. Two Pointers
3. Sliding Window
4. Stack
5. Binary Search
6. Linked List
7. Trees
8. Tries
9. Backtracking
10. Heap / Priority Queue
11. Graphs
12. 1D Dynamic Programming
13. Intervals
14. Greedy
15. Advanced Graphs
16. 2D Dynamic Programming
17. Bit Manipulation
18. Math & Geometry

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📊 Progress (Arrays & Hashing)

• Total Solved: 4 / 9
  • Easy: 3
  • Medium: 1

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🧩 Arrays & Hashing

1. Valid Anagram

• Difficulty:
• Problem Link: NeetCode
• Approach:
  • Use a hash map (array) to count character frequencies in s.
  • Decrease count for each character in t.
  • If all counts reduce to zero → strings are anagrams.
• Time Complexity: O(n + m)
• Space Complexity: O(1)
• Solution: anagram.js

2. Contains Duplicate

• Difficulty:
• Problem Link: NeetCode
• Approach:
  • Use a Set to track seen numbers.
  • Return true if a duplicate is found, otherwise false.
• Time Complexity: O(n)
• Space Complexity: O(n)
• Solution: duplication.js

3. Group Anagrams

• Difficulty:
• Problem Link: NeetCode
• Approach:
  • Count character frequencies for each word and use as a key in a Map.
  • Group words with the same key together.
• Solution: groupanagram.js

4. Two Sum

• Difficulty:
• Problem Link: LeetCode
• Approach:
  • Use a Map to store seen numbers and their indices.
  • For each number, check if target - current exists.
  • Return indices if found.
• Time Complexity: O(n)
• Space Complexity: O(n)
• Solution: twosum.js

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🛠️ Tools & Technologies

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📌 How to Use

1. Clone the repository:

git clone https://github.com/Nitesh0434/DSA-Practice.git
# Fri Sep 12 11:11:44 PM +0545 2025