Master DSA with Resources, 6 week roadmap and problems

I suffered with DSA and coding for a long time. Especially even when I was given patterns that should have helped me. It wasn’t until I spoke to my friend who was a senior engineer at Netflix that it got resolved. And he helped me with 3 key things

1. A Pyramid based approach on problems with most asked patterns vs least asked patterns which helped me practice accordingly.

2. 35+ resources and patterns which helped me understand each pattern properly.

3. Problems for each pattern.

Pyramid based system with green being most asked and red being least asked.

RESOURCES TO UNDERSTAND EACH PATTERN

1. Dynamic Programming

Link 1
DP for beginners
DP problems orderwise

2. Linked List
Linked List Mastery
Linked List Study Guide

3. Prefix Sum
Explainer

4. Bits Manipulation
All types of explanation

5. Strings
Important String Questions

6. Sliding Window
Cheatsheet

7. Back Tracking
Level wise problems
Approach to solve backtracking

8. Two Pointers
Strategy
Master two pointer

9. Stack & Queue
Approach
Monotonic Stacks and Queues

10. Heap
Understanding 4 patterns for HEAP
Patterns for HEAPS

11. Binary Search
Binary Search Template
Binary search algorithm guide

12. Graphs
Graph Algorithms
Graph Mastery
Disjoint Set Guide

13. Tree
Pattern
Master Tree Patterns
Binary Tree Guide

14. Recursion
Become Master in Recursion

15. Greedy
ABCs of Greedy

6 WEEK ROADMAP

WEEK 1 : Two Pointers , Fast & Slow pointers, Sliding Window and Merge Intervals

1. Introduction

2. Pair with Target Sum (easy) LeetCode

3. Remove Duplicates (easy) LeetCode LeetCode LeetCode LeetCode LeetCode

4. Squaring a Sorted Array (easy) LeetCode

5. Triplet Sum to Zero (medium) LeetCode

6. Triplet Sum Close to Target (medium) LeetCode

7. Triplets with Smaller Sum (medium) LintCode

8. Subarrays with Product Less than a Target (medium) LeetCode

9. Dutch National Flag Problem (medium) CoderByte

10. Problem Challenge 1: Quadruple Sum to Target (medium) Leetcode

11. Problem Challenge 2: Comparing Strings containing Backspaces (medium) Leetcode

12. Problem Challenge 3: Minimum Window Sort (medium) Leetcode Ideserve

13. Introduction emre.me

14. LinkedList Cycle (easy) Leetcode

15. Start of LinkedList Cycle (medium) Leetcode

16. Happy Number (medium) Leetcode

17. Middle of the LinkedList (easy) Leetcode

18. Problem Challenge 1: Palindrome LinkedList (medium) Leetcode

19. Problem Challenge 2: Rearrange a LinkedList (medium) Leetcode

20. Problem Challenge 3: Cycle in a Circular Array (hard) Leetcode

1. Introduction

2. Maximum Sum Subarray of Size K (easy)

3. Smallest Subarray with a given sum (easy) Educative.io

4. Longest Substring with K Distinct Characters (medium) Educative.io

5. Fruits into Baskets (medium) LeetCode

6. No-repeat Substring (hard) LeetCode

7. Longest Substring with Same Letters after Replacement (hard) LeetCode

8. Longest Subarray with Ones after Replacement (hard) LeetCode

9. Problem Challenge 1: Permutation in a String (hard) Leetcode

10. Problem Challenge 2: String Anagrams (hard) Leetcode

11. Problem Challenge 3: Smallest Window containing Substring (hard) Leetcode

12. Problem Challenge 4: Words Concatenation (hard) Leetcode

13. Introduction Educative.io

14. Merge Intervals (medium) Educative.io

15. Insert Interval (medium) Educative.io

16. Intervals Intersection (medium) Educative.io

17. Conflicting Appointments (medium) Geeksforgeeks

18. Problem Challenge 1: Minimum Meeting Rooms (hard) Lintcode

19. Problem Challenge 2: Maximum CPU Load (hard) Geeksforgeeks

20. Problem Challenge 3: Employee Free Time (hard) CoderTrain

WEEK 2: Cyclic Sort , In-place reversal of Linked List , Stack and Monotonic Stack

1. Introduction emre.me

2. Cyclic Sort (easy) Geeksforgeeks

3. Find the Missing Number (easy) Leetcode

4. Find all Missing Numbers (easy) Leetcode

5. Find the Duplicate Number (easy) Leetcode

6. Find all Duplicate Numbers (easy) Leetcode

7. Problem Challenge 1: Find the Corrupt Pair (easy) TheCodingSimplified

8. Problem Challenge 2: Find the Smallest Missing Positive Number (medium) Leetcode

9. Problem Challenge 3: Find the First K Missing Positive Numbers (hard) TheCodingSimplified

10. Introduction emre.me

11. Reverse a LinkedList (easy) Leetcode

12. Reverse a Sub-list (medium) Leetcode

13. Reverse every K-element Sub-list (medium) Leetcode

14. Problem Challenge 1: Reverse alternating K-element Sub-list (medium) Geeksforgeeks

15. Problem Challenge 2: Rotate a LinkedList (medium) Leetcode

1. Introduction to Stack (Operations, Implementation, Applications)

2. Balanced Parentheses Leetcode

3. Reverse a String

4. Decimal to Binary Conversion

5. Next Greater Element Leetcode - I Leetcode -II Leetcode - III (Hard)

6. Sorting a Stack

7. Simplify Path Leetcode

8. Introduction to Monotonic Stack

9. Next Greater Element (easy) Leetcode - I Leetcode -II Leetcode - III (Hard)

10. Daily Temperatures (easy) Leetcode

11. Remove Nodes From Linked List (easy) Leetcode

12. Remove All Adjacent Duplicates In String (easy) Leetcode

13. Remove All Adjacent Duplicates in String II (medium) Leetcode

14. Remove K Digits (hard) Leetcode

WEEK 3: Hash Maps , Tree : BFS, Tree : DFS and Graph

1. Introduction (Hashing, Hash Tables, Issues)

2. First Non-repeating Character (easy) Leetcode

3. Largest Unique Number (easy) Leetcode+

4. Maximum Number of Balloons (easy) Leetcode

5. Longest Palindrome(easy) Leetcode

6. Ransom Note (easy) Leetcode

7. Binary Tree Level Order Traversal (easy) Leetcode

8. Reverse Level Order Traversal (easy) Leetcode

9. Zigzag Traversal (medium) Leetcode

10. Level Averages in a Binary Tree (easy) Leetcode

11. Minimum Depth of a Binary Tree (easy) Leetcode

12. Maximum Depth of a Binary Tree (easy) Leetcode

13. Level Order Successor (easy) Geeksforgeeks

14. Connect Level Order Siblings (medium) Leetcode

15. Problem Challenge 1: Connect All Level Order Siblings (medium) Educative

16. Problem Challenge 2: Right View of a Binary Tree (easy) Leetcode

1. Introduction

2. Binary Tree Path Sum (easy) Leetcode

3. All Paths for a Sum (medium) Leetcode

4. Sum of Path Numbers (medium) Leetcode

5. Path With Given Sequence (medium) Geeksforgeeks

6. Count Paths for a Sum (medium) Leetcode

7. Problem Challenge 1: Tree Diameter (medium) Leetcode

8. Problem Challenge 2: Path with Maximum Sum (hard) Leetcode

9. Introduction to Graph (Representations, Abstract Data Type (ADT))

10. Graph Traversal: Depth First Search(DFS)

11. Graph Traversal: Breadth First Search (BFS)

12. Find if Path Exists in Graph(easy) Leetcode

13. Number of Provinces (medium) Leetcode

14. Minimum Number of Vertices to Reach All Nodes(medium) Leetcode

WEEK 4: Island , Two Heaps, Subsets and Modified Binary Search

1. Introduction to Island Pattern

2. Number of Islands (easy) Leetcode

3. Biggest Island (easy)

4. Flood Fill (easy) Leetcode

5. Number of Closed Islands (easy) Leetcode

6. Find the Median of a Number Stream (medium) Leetcode

7. Sliding Window Median (hard) Leetcode

8. Maximize Capital (hard) Leetcode

9. *Maximum Sum Combinations (medium) InterviewBit

1. Introduction Educative.io

2. Subsets (easy) Educative.io

3. Subsets With Duplicates (easy) Educative.io

4. Permutations (medium) Educative.io

5. Introduction Complete Pattern Theory and Solutions

6. Order-agnostic Binary Search (easy) Geeksforgeeks

7. Ceiling of a Number (medium) Geeksforgeeks-Ceil Geeksforgeeks-Floor

8. Next Letter (medium) Leetcode

9. Number Range (medium) Leetcode

10. Search in a Sorted Infinite Array (medium) Leetcode

11. Minimum Difference Element (medium): Find the floor & ceil take the difference, minimum would be the ans

12. Bitonic Array Maximum (easy) Geeksforgeeks

13. Problem Challenge 1: Search Bitonic Array (medium) Leetcode

14. Problem Challenge 2: Search in Rotated Array (medium) Leetcode

15. Problem Challenge 3: Rotation Count (medium) Geeksforgeeks

16. *Search a 2D Matrix (medium) Leetcode

17. *Minimum Number of Days to Make m Bouquets (medium) Leetcode

18. *Koko Eating Bananas (medium) Leetcode

19. *Capacity To Ship Packages Within D Days (medium) Leetcode

20. *Median of Two Sorted Arrays (hard) Leetcode

WEEK 5: Bitwise XOR , Top K Elements , K-way merge and Greedy Sort

1. Single Number (easy)

2. Two Single Numbers (medium)

3. Complement of Base 10 Number (medium)

4. Problem Challenge 1: Flip and Invert an Image (hard)

5. Introduction

6. Top 'K' Numbers (easy) Solution

7. Kth Smallest Number (easy)

8. 'K' Closest Points to the Origin (easy) Leetcode

9. Connect Ropes (easy)

10. Top 'K' Frequent Numbers (medium)

11. Frequency Sort (medium)

12. Kth Largest Number in a Stream (medium) Leetcode

1. Merge K Sorted Lists (medium) Leetcode

2. Kth Smallest Number in M Sorted Lists (Medium) Geeksforgeeks

3. Kth Smallest Number in a Sorted Matrix (Hard) Educative.io

4. Smallest Number Range (Hard) Leetcode

5. Valid Palindrome II (easy) Leetcode

6. Maximum Length of Pair Chain (medium) Leetcode

7. Minimum Add to Make Parentheses Valid (medium) Leetcode

8. Remove Duplicate Letters (medium) Leetcode

9. Largest Palindromic Number (Medium) Leetcode

10. Removing Minimum and Maximum From Array (medium) Leetcode

WEEK 6: 0/1 Knapsack , BackTracking, Trie and Topological Sort

1. 0/1 Knapsack (medium) Geeksforgeeks

2. Equal Subset Sum Partition (medium) Leetcode

3. Subset Sum (medium) Geeksforgeeks

4. Minimum Subset Sum Difference (hard) Geeksforgeeks

5. Combination Sum (medium) Leetcode - I Leetcode - II Leetcode - III Leetcode - IV

6. Word Search (medium) Leetcode - I Leetcode - II (Hard)

7. Sudoku Solver (hard) Leetcode

8. Factor Combinations (medium) Leetcode+

9. Split a String Into the Max Number of Unique Substrings (medium) Leetcode

1. Implement Trie (Prefix Tree) (medium) Leetcode

2. Index Pairs of a String (easy) Leetcode+

3. Design Add and Search Words Data Structure (medium) Leetcode

4. Extra Characters in a String (medium) Leetcode

5. Search Suggestions System (medium) Leetcode

6. Topological Sort (medium) Youtube

7. Tasks Scheduling (medium) Leetcode-Similar

8. Tasks Scheduling Order (medium) Leetcode-Similar

9. All Tasks Scheduling Orders (hard) Leetcode-Similar

10. Alien Dictionary (hard) Leetcode

11. Problem Challenge 1: Reconstructing a Sequence (hard) Leetcode

12. Problem Challenge 2: Minimum Height Trees (hard) Leetcode

WEEK 7 : Union Find , Ordered Set and Multi-thread (optional)

1. Redundant Connection (medium) Leetcode - I Leetcode - II (Hard)

2. Number of Provinces (medium) Leetcode

3. Is Graph Bipartite? (medium) Leetcode

4. Path With Minimum Effort (medium) Leetcode

5. Merge Similar Items (easy) Leetcode

6. 132 Pattern (medium) Leetcode

7. My Calendar I (medium) Leetcode Leetcode - II Leetcode - III (Hard)

I provide all my resources and information for free and I hope that even 1% of this can help you in your career. At the same time, I do this all by myself and don’t have anyone to help or any marketing budget to work with. So, if you found this article helpful, consider supporting me by making a donation through buymeacoffee , becoming a paid member of substack or susbcribing to my Youtube page.