🚀 LeetCode Solutions

This repository contains my LeetCode problem solutions, automatically synced using the LeetHub extension.

LeetHub connects LeetCode with GitHub and automatically uploads solutions whenever a problem is solved. Each solution includes the problem name, runtime performance, memory usage, and solution code.

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📌 About This Repository

• Solutions are automatically pushed using LeetHub

• Contains problems solved on LeetCode

• Organized by difficulty level

• Each problem includes:

  • Problem title
  • Solution code
  • Runtime performance
  • Memory usage
  • Problem metadata

This repository helps track my Data Structures and Algorithms (DSA) practice and consistency.

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🧠 Topics Covered

Some of the key DSA concepts practiced in this repository include:

• Arrays
• Strings
• Linked Lists
• Stacks & Queues
• Hashing
• Greedy Algorithms

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📂 Repository Structure

DSACore/
│
└── LeetCode/
    │
    ├── Easy/
    │   └── problem-name/
    │
    ├── Medium/
    │   └── problem-name/
    │
    └── Hard/
        └── problem-name/

Each problem folder contains:

• Solution implementation
• Runtime performance
• Memory usage
• Problem metadata automatically generated by LeetHub

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📈 Goal

The goal of this repository is to:

• Maintain consistency in solving DSA problems
• Improve problem-solving and algorithmic thinking
• Prepare for software engineering interviews and coding assessments

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👨‍💻 Author

Ansh Agarwal

• Computer Science Engineering Student
• Practicing Data Structures & Algorithms
• Preparing for Software Engineering roles

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⭐ If you find this repository useful, feel free to star it.

LeetCode Topics

Math

Problem Name	Difficulty
0012-integer-to-roman	Medium
0050-powx-n	Medium
0779-k-th-symbol-in-grammar	Medium
1688-count-of-matches-in-tournament	Easy
1759-count-number-of-homogenous-substrings	Medium
1823-find-the-winner-of-the-circular-game	Medium
1922-count-good-numbers	Medium

Recursion

Problem Name	Difficulty
0021-merge-two-sorted-lists	Easy
0050-powx-n	Medium
0206-reverse-linked-list	Easy
0779-k-th-symbol-in-grammar	Medium
1823-find-the-winner-of-the-circular-game	Medium
1922-count-good-numbers	Medium

Two Pointers

Problem Name	Difficulty
0015-3sum	Medium
0028-find-the-index-of-the-first-occurrence-in-a-string	Easy
0125-valid-palindrome	Easy
0443-string-compression	Medium
2109-adding-spaces-to-a-string	Medium

String

Problem Name	Difficulty
0012-integer-to-roman	Medium
0017-letter-combinations-of-a-phone-number	Medium
0020-valid-parentheses	Easy
0022-generate-parentheses	Medium
0028-find-the-index-of-the-first-occurrence-in-a-string	Easy
0038-count-and-say	Medium
0076-minimum-window-substring	Hard
0079-word-search	Medium
0093-restore-ip-addresses	Medium
0125-valid-palindrome	Easy
0242-valid-anagram	Easy
0387-first-unique-character-in-a-string	Easy
0389-find-the-difference	Easy
0443-string-compression	Medium
0520-detect-capital	Easy
0606-construct-string-from-binary-tree	Medium
0692-top-k-frequent-words	Medium
0859-buddy-strings	Easy
0944-delete-columns-to-make-sorted	Easy
1160-find-words-that-can-be-formed-by-characters	Easy
1496-path-crossing	Easy
1544-make-the-string-great	Easy
1662-check-if-two-string-arrays-are-equivalent	Easy
1704-determine-if-string-halves-are-alike	Easy
1759-count-number-of-homogenous-substrings	Medium
1832-check-if-the-sentence-is-pangram	Easy
2109-adding-spaces-to-a-string	Medium
2264-largest-3-same-digit-number-in-string	Easy

Hash Table

Problem Name	Difficulty
0012-integer-to-roman	Medium
0017-letter-combinations-of-a-phone-number	Medium
0037-sudoku-solver	Hard
0076-minimum-window-substring	Hard
0242-valid-anagram	Easy
0387-first-unique-character-in-a-string	Easy
0389-find-the-difference	Easy
0496-next-greater-element-i	Easy
0692-top-k-frequent-words	Medium
0859-buddy-strings	Easy
1160-find-words-that-can-be-formed-by-characters	Easy
1496-path-crossing	Easy
1832-check-if-the-sentence-is-pangram	Easy

Counting

Problem Name	Difficulty
0387-first-unique-character-in-a-string	Easy
0692-top-k-frequent-words	Medium
1160-find-words-that-can-be-formed-by-characters	Easy
1704-determine-if-string-halves-are-alike	Easy

Array

Problem Name	Difficulty
0015-3sum	Medium
0037-sudoku-solver	Hard
0039-combination-sum	Medium
0040-combination-sum-ii	Medium
0051-n-queens	Hard
0053-maximum-subarray	Medium
0078-subsets	Medium
0079-word-search	Medium
0090-subsets-ii	Medium
0209-minimum-size-subarray-sum	Medium
0496-next-greater-element-i	Easy
0503-next-greater-element-ii	Medium
0643-maximum-average-subarray-i	Easy
0692-top-k-frequent-words	Medium
0724-find-pivot-index	Easy
0867-transpose-matrix	Easy
0944-delete-columns-to-make-sorted	Easy
1160-find-words-that-can-be-formed-by-characters	Easy
1464-maximum-product-of-two-elements-in-an-array	Easy
1662-check-if-two-string-arrays-are-equivalent	Easy
1823-find-the-winner-of-the-circular-game	Medium
1913-maximum-product-difference-between-two-pairs	Easy
2109-adding-spaces-to-a-string	Medium
2706-buy-two-chocolates	Easy

Stack

Problem Name	Difficulty
0020-valid-parentheses	Easy
0155-min-stack	Medium
0225-implement-stack-using-queues	Easy
0496-next-greater-element-i	Easy
0503-next-greater-element-ii	Medium
1544-make-the-string-great	Easy

Simulation

Problem Name	Difficulty
0867-transpose-matrix	Easy
1688-count-of-matches-in-tournament	Easy
1823-find-the-winner-of-the-circular-game	Medium
2109-adding-spaces-to-a-string	Medium

Backtracking

Problem Name	Difficulty
0017-letter-combinations-of-a-phone-number	Medium
0022-generate-parentheses	Medium
0037-sudoku-solver	Hard
0039-combination-sum	Medium
0040-combination-sum-ii	Medium
0051-n-queens	Hard
0078-subsets	Medium
0079-word-search	Medium
0090-subsets-ii	Medium
0093-restore-ip-addresses	Medium

Dynamic Programming

Problem Name	Difficulty
0022-generate-parentheses	Medium
0053-maximum-subarray	Medium

String Matching

Problem Name	Difficulty
0028-find-the-index-of-the-first-occurrence-in-a-string	Easy

Trie

Problem Name	Difficulty
0692-top-k-frequent-words	Medium

Sorting

Problem Name	Difficulty
0015-3sum	Medium
0242-valid-anagram	Easy
0389-find-the-difference	Easy
0692-top-k-frequent-words	Medium
1464-maximum-product-of-two-elements-in-an-array	Easy
1913-maximum-product-difference-between-two-pairs	Easy
2706-buy-two-chocolates	Easy

Heap (Priority Queue)

Problem Name	Difficulty
0692-top-k-frequent-words	Medium
1464-maximum-product-of-two-elements-in-an-array	Easy

Bucket Sort

Problem Name	Difficulty
0692-top-k-frequent-words	Medium

Bit Manipulation

Problem Name	Difficulty
0078-subsets	Medium
0090-subsets-ii	Medium
0389-find-the-difference	Easy
0779-k-th-symbol-in-grammar	Medium

Tree

Problem Name	Difficulty
0606-construct-string-from-binary-tree	Medium

Depth-First Search

Problem Name	Difficulty
0079-word-search	Medium
0606-construct-string-from-binary-tree	Medium

Binary Tree

Problem Name	Difficulty
0606-construct-string-from-binary-tree	Medium

Queue

Problem Name	Difficulty
0225-implement-stack-using-queues	Easy
0387-first-unique-character-in-a-string	Easy
1823-find-the-winner-of-the-circular-game	Medium

Matrix

Problem Name	Difficulty
0037-sudoku-solver	Hard
0079-word-search	Medium
0867-transpose-matrix	Easy

Binary Search

Problem Name	Difficulty
0209-minimum-size-subarray-sum	Medium
0374-guess-number-higher-or-lower	Easy

Interactive

Problem Name	Difficulty
0374-guess-number-higher-or-lower	Easy

Greedy

Problem Name	Difficulty
2706-buy-two-chocolates	Easy

Sliding Window

Problem Name	Difficulty
0076-minimum-window-substring	Hard
0209-minimum-size-subarray-sum	Medium
0643-maximum-average-subarray-i	Easy

Prefix Sum

Problem Name	Difficulty
0209-minimum-size-subarray-sum	Medium
0724-find-pivot-index	Easy

Divide and Conquer

Problem Name	Difficulty
0053-maximum-subarray	Medium

Linked List

Problem Name	Difficulty
0021-merge-two-sorted-lists	Easy
0206-reverse-linked-list	Easy

Design

Problem Name	Difficulty
0155-min-stack	Medium
0225-implement-stack-using-queues	Easy

Monotonic Stack

Problem Name	Difficulty
0496-next-greater-element-i	Easy
0503-next-greater-element-ii	Medium