theWhiteFoxDev
LeetCode: Starting Over NeetCode 150

LeetCode: Starting Over NeetCode 150

Authors

Introduction

Join me on an adventure of transformation as I navigate the challenging yet rewarding path to mastering problem-solving skills through NeetCode. Whether you're preparing for coding interviews or looking to improve your programming abilities, I believe this structured approach to tackling 150 NeetCode problems is the key to success.

Introduction-approach.svg

Why Start Over?

After reflecting on my previous attempts, I realized the need for a more organized approach. By categorizing problems and focusing on Data Structures and Algorithms (DSA), I can build a strong foundation and solve challenges more efficiently.

I came to this realization the hard way, while working through 28 Days "Leeter" Part 1 & Part 2 LeetCode problems. This led me to reassess my approach, and I decided to start over. You can read more about my approach solving LeetCode problems.

Categories and Patterns

By categorizing problems into specific problem-solving strategies and algorithms/patterns, it becomes easier to focus on mastering one type of problem at a time. Grouping them in this way leads to a more efficient and effective learning process.

Arrays & Hashing

First up, Arrays & Hashing, check out my post on Arrays and Hashing with TypeScript for a brief outline of what they are and why we use them. You can also click the links below to go directly to the NeetCode problems and solutions that I have tackled so far.

  • Contains Duplicate checks if there are any duplicates in an array.
  • Valid Anagram determines if two strings are anagrams.
  • Two Sum finds two numbers in an array that add up to a specific target.
  • Group Anagrams groups anagrams together in an array of strings.
  • Top K Frequent Elements identifies the k most frequent elements in an array.
  • Encode and Decode Strings: Encodes a list of strings to a single string and decodes it back to the list.
  • Product of Array Except Self: Calculates the product of all elements in the array except the current one for each element.
  • Valid Sudoku: Validates whether a given Sudoku board configuration is valid.

Two Pointers

  • Valid Palindrome
  • Two Sum II
  • 3Sum
  • Container with Most Water
  • Trapping Rain Water

Sliding Window

  • Best Time to Buy & Sell Stock
  • Longest Substring Without Repeating Characters
  • Longest Repeating Character Replacement
  • Permutation in String
  • Minimum Window Substring
  • Sliding Window Maximum

Stack

  • Valid Parentheses
  • Min Stack
  • Evaluate Reverse Polish Notation
  • Generate Parentheses
  • Daily Temperatures
  • Car Fleet
  • Largest Rectangle in Histogram

Binary Search

  • Search a 2D Matrix
  • Koko Eating Bananas
  • Search Rotated Sorted Array
  • Find Minimum in Rotated Sorted Array
  • Time Based Key-Value Store
  • Binary Search Find Median of Two Sorted Arrays

Backtracking

  • Reverse Linked List
  • Merge Two Linked Lists
  • Reorder List
  • Remove Nth Node from End of List
  • Copy List with Random Pointer
  • Add Two Numbers
  • Linked List Cycle
  • Find the Duplicate Number
  • LRU Cache
  • Merge K Sorted Lists
  • Reverse Nodes in K-Group

Graphs

  • Number of Islands
  • Clone Graph
  • Max Area of Island
  • Pacific Atlantic Waterflow
  • Surrounded Regions
  • Rotting Oranges
  • Walls and Gates
  • Course Schedule
  • Course Schedule II
  • Redundant Connection
  • Number of Connected Components in Graph
  • Graph Valid Tree
  • Word Ladder

Advanced Graphs

  • Reconstruct Itinerary
  • Min Cost to Connect all Points
  • Network Delay Time
  • Swim in Rising Water
  • Alien Dictionary
  • Cheapest Flights with K Stops

1-D Dynamic Programming

  • Climbing Stairs
  • Min Cost Climbing Stairs
  • House Robber
  • House Robber II
  • Longest Palindroming Substring
  • Palindrome Substrings
  • Decode Ways
  • Coin Change
  • Maximum Product Subarray
  • Word Break
  • Longest Increasing Subsequence
  • Partition Equal Subset Sum

2-D Dynamic Programming

  • Unique Paths
  • Longest Common Subsequence
  • Best Time to Buy/Sell Stock With Cooldown
  • Coin Change II
  • Target SUm
  • Interleaving String
  • Longest Increasing Path in a Matrix
  • Distinct Subsequences
  • Edit Distance
  • Burst Balloons
  • Regular Expression Matching

Greedy

  • Maximum Subarray
  • Jump Game
  • Jump Game II
  • Gas Station
  • Hand of Straights
  • Merge Triplets to Form Target Triplet
  • Partition Labels
  • Valid Parenthesis String

Intervals

  • Insert Interval
  • Merge Intervals
  • Non-Overlapping Intervals
  • Meeting Rooms
  • Meeting Rooms II
  • Minimum Interval to Include Each Query

Math & Geometry

  • Rotate Image
  • Spiral Matrix
  • Set Matrix Zeroes
  • Happy Number
  • Plus One
  • Pow(x, n)
  • Multiply Strings
  • Detect Squares

Bit Manipulation

  • Single Number
  • Number of 1 Bits
  • Counting Bits
  • Reverse Bits
  • Missing Number
  • Sum of Two Integers
  • Reverse Integer

Importance of Repetition

As highlighted in the NeeCode video on learning maths, and something that resonated with me (how I certainly learned maths), repetition plays a crucial role in reinforcing concepts and techniques. The same principle applies to learning coding problems. By repeatedly practicing various types of problems, you can achieve the following benefits:

Understanding Patterns: Recognizing common patterns and techniques used in solving problems.

Improving Efficiency: Developing the ability to solve problems more quickly and accurately.

Building Confidence: Gaining confidence in tackling new and complex problems by building a strong foundation.

This structured and repetitive approach ensures a comprehensive understanding and mastery over different types of LeetCode problems.

Reference

Photo by Lin Mei on Unsplash