Problem Journey

Welcome Back, Engineer

Mastering the 5 pillars of Software Engineering. Track my progress.

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DSA

Data Structures & Algorithms

53 Problems
🏗️

System Design

Scalable Architectures

1 Problems
💾

Database

SQL & NoSQL optimization

1 Problems
⚡

JavaScript

Frontend & JS Internals

1 Problems
📐

LLD

Low-Level Design Patterns

0 Problems
🎯

DSA & OOP

Practice Problems

3 Problems

Latest Solved

143. Reorder List

DSA LeetCode NeetCode Linked List Two Pointers Stack Queue 📅 Mar 15
Medium

19. Remove Nth Node From End of List

DSA LeetCode NeetCode Linked List Two Pointers 📅 Mar 15
Medium

141. Linked List Cycle Detection

DSA LeetCode NeetCode Linked List Two Pointers 📅 Mar 15
Easy

205. Isomorphic Strings

DSA LeetCode Hash Table String 📅 Mar 15
Easy

138. Copy List with Random Pointer

DSA LeetCode NeetCode Hash Table Linked List 📅 Mar 15
Medium

2. Add Two Numbers

DSA LeetCode NeetCode Linked List Math Recursion 📅 Mar 15
Medium

Reverse Linked List

DSA LeetCode NeetCode Linked List Recursion 📅 Mar 14
Easy

Merge Two Sorted Linked Lists

DSA LeetCode NeetCode Linked List Recursion 📅 Mar 14
Easy

Median of Two Sorted Arrays

DSA LeetCode NeetCode Array Binary Search Divide and Conquer 📅 Mar 14
Hard

Search a 2D Matrix

DSA NeetCode Array Binary Search Matrix 📅 Mar 07
Medium

Find Minimum in Rotated Sorted Array

DSA NeetCode Array Binary Search 📅 Mar 07
Medium

Koko Eating Bananas

DSA NeetCode Array Binary Search 📅 Mar 07
Medium

Largest Rectangle In Histogram

DSA NeetCode Array Stack Monotonic Stack 📅 Mar 06
Hard

Car Fleet

DSA NeetCode Array Stack Sorting Monotonic Stack 📅 Mar 06
Medium

Valid Parentheses

DSA NeetCode String Stack 📅 Mar 04
Easy

Sliding Window Maximum

DSA NeetCode Array Sliding Window Queue Monotonic Queue 📅 Mar 04
Hard

Minimum Window Substring

DSA NeetCode String Sliding Window Hash Table 📅 Mar 04
Hard

Evaluate Reverse Polish Notation

DSA NeetCode Array Math Stack 📅 Mar 04
Medium

Daily Temperatures

DSA NeetCode Array Stack Monotonic Stack 📅 Mar 04
Medium

Permutation in String

DSA NeetCode String Sliding Window Hash Table 📅 Mar 03
Medium

Longest Repeating Character Replacement

DSA NeetCode String Sliding Window Hash Table 📅 Mar 03
Medium

Longest Substring Without Repeating Characters

DSA NeetCode String Sliding Window Hash Set 📅 Feb 27
Medium

Design a Parking Lot System

DSA & OOP Design OOP System Design 📅 Feb 24
Medium

LRU Cache

DSA & OOP Design Hash Table Linked List OOP 📅 Feb 24
Medium

Design HashMap

DSA & OOP Design Array Hash Table OOP 📅 Feb 24
Easy

Best Time to Buy and Sell Stock

DSA LeetCode NeetCode Array Dynamic Programming 📅 Feb 22
Easy

Trapping Rain Water

DSA NeetCode Array Two Pointers Dynamic Programming 📅 Feb 21
Hard

Three Integer Sum

DSA NeetCode Array Two Pointers Sorting 📅 Feb 21
Medium

Container With Most Water

DSA NeetCode Array Two Pointers Greedy 📅 Feb 21
Medium

Two Integer Sum II

DSA NeetCode Array Two Pointers 📅 Feb 19
Medium

Valid Sudoku

DSA NeetCode Array Hash Table Matrix 📅 Feb 18
Medium

Valid Palindrome

DSA NeetCode String Two Pointers 📅 Feb 18
Easy

Longest Consecutive Sequence

DSA NeetCode Array Hash Table Union Find 📅 Feb 18
Medium

Top K Frequent Elements

DSA NeetCode Array Hash Table Heap (Priority Queue) 📅 Feb 17
Medium

Product of Array Except Self

DSA NeetCode Array Prefix Sum 📅 Feb 17
Medium

String Encode and Decode

DSA NeetCode String Design Array 📅 Feb 17
Medium

Valid Parenthesis Check

DSA Stack String 📅 Feb 16
Easy

Find the Unique Element in an Array

DSA Array 📅 Feb 16
Easy

String Multiplication

DSA String Math Hash Map 📅 Feb 16
Easy

Match String Patterns

DSA Hash Map String 📅 Feb 16
Easy

Longest Continuous Numbers in an Array

DSA Array Sorting 📅 Feb 16
Medium

Second Largest Element

DSA Array 📅 Feb 15
Easy

Group Anagrams

DSA NeetCode Array Hash Table String Sorting 📅 Feb 14
Medium

Valid Anagram

DSA NeetCode String Hash Table Sorting 📅 Feb 12
Easy

Two Sum

DSA NeetCode Array Hash Table 📅 Feb 12
Easy

Contains Duplicate

DSA NeetCode Array Hash Table 📅 Feb 11
Easy

Evaluate Reverse Polish Notation

DSA LeetCode Array Stack Math 📅 Feb 01
Medium

Build an Array With Stack Operations

DSA LeetCode Array Stack Simulation 📅 Feb 01
Easy

How Many Numbers Are Smaller Than the Current Number

DSA LeetCode Array Hash Table Sorting Counting Sort 📅 Jan 31
Medium

Find All Numbers Disappeared in an Array

DSA LeetCode Array Hash Table 📅 Jan 31
Easy

Set Mismatch

DSA LeetCode Array Hash Table Bit Manipulation Sorting 📅 Jan 30
Easy

Max Consecutive Ones

DSA LeetCode Array 📅 Jan 29
Easy

Shuffle the Array

DSA LeetCode Array 📅 Jan 28
Easy

Concatenation of Array

DSA LeetCode Array 📅 Jan 28
Easy

Design URL Shortener

System Design System Design Scalability 📅 Jan 24
Medium

Memoize

JavaScript JavaScript Closure Recursion 📅 Jan 24
Medium

Combine Two Tables

Database Database SQL 📅 Jan 24
Easy

Two Sum

DSA LeetCode Array Hash Table 📅 Jan 23
Easy

Title

DSA LeetCode NeetCode Array 📅 Jan 01
Easy

Difficulty Levels

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