Grokking the Coding Interview: Patterns for Coding Questions

Course Overview

Coding interviews are getting harder every day. A few years back, brushing up on key data structures and going through 50-75 coding interview questions was more than enough prep for an interview. Today, everyone has access to massive sets of coding problems, and they've gotten more dif... See More

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How You'll Learn

Hands-on coding environments

You don’t get better at swimming by watching others. Coding is no different. Practice as you learn with live code environments inside your browser.

Faster than videos

Videos are holding you back. The average video tutorial is spoken at 150 words per minute, while you can read at 250. That‘s why our courses are text-based.

No set-up required

Start learning immediately instead of fiddling with SDKs and IDEs. It‘s all on the cloud.

Progress you can show

Built in assessments let you test your skills. Completion certificates let you show them off.

Hands-on coding environments

You don’t get better at swimming by watching others. Coding is no different. Practice as you learn with live code environments inside your browser.

Faster than videos

Videos are holding you back. The average video tutorial is spoken at 150 words per minute, while you can read at 250. That‘s why our courses are text-based.

No set-up required

Start learning immediately instead of fiddling with SDKs and IDEs. It‘s all on the cloud.

Progress you can show

Built in assessments let you test your skills. Completion certificates let you show them off.

Course Contents

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1. Introduction

Who should take this course?

Course Overview

2. Pattern: Sliding Window

Introduction

Maximum Sum Subarray of Size K (easy)

Smallest Subarray with a given sum (easy)

Longest Substring with K Distinct Characters (medium)

Fruits into Baskets (medium)

No-repeat Substring (hard)

Longest Substring with Same Letters after Replacement (hard)

Longest Subarray with Ones after Replacement (hard)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

Problem Challenge 3

Solution Review: Problem Challenge 3

Problem Challenge 4

Solution Review: Problem Challenge 4

3. Pattern: Two Pointers

Introduction

Pair with Target Sum (easy)

Remove Duplicates (easy)

Squaring a Sorted Array (easy)

Triplet Sum to Zero (medium)

Triplet Sum Close to Target (medium)

Triplets with Smaller Sum (medium)

Subarrays with Product Less than a Target (medium)

Dutch National Flag Problem (medium)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

Problem Challenge 3

Solution Review: Problem Challenge 3

4. Pattern: Fast & Slow pointers

Introduction

LinkedList Cycle (easy)

Start of LinkedList Cycle (medium)

Happy Number (medium)

Middle of the LinkedList (easy)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

Problem Challenge 3

Solution Review: Problem Challenge 3

5. Pattern: Merge Intervals

Introduction

Merge Intervals (medium)

Insert Interval (medium)

Intervals Intersection (medium)

Conflicting Appointments (medium)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

Problem Challenge 3

Solution Review: Problem Challenge 3

6. Pattern: Cyclic Sort

Introduction

Cyclic Sort (easy)

Find the Missing Number (easy)

Find all Missing Numbers (easy)

Find the Duplicate Number (easy)

Find all Duplicate Numbers (easy)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

Problem Challenge 3

Solution Review: Problem Challenge 3

7. Pattern: In-place Reversal of a LinkedList

Introduction

Reverse a LinkedList (easy)

Reverse a Sub-list (medium)

Reverse every K-element Sub-list (medium)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

8. Pattern: Tree Breadth First Search

Introduction

Binary Tree Level Order Traversal (easy)

Reverse Level Order Traversal (easy)

Zigzag Traversal (medium)

Level Averages in a Binary Tree (easy)

Minimum Depth of a Binary Tree (easy)

Level Order Successor (easy)

Connect Level Order Siblings (medium)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

9. Pattern: Tree Depth First Search

Introduction

Binary Tree Path Sum (easy)

All Paths for a Sum (medium)

Sum of Path Numbers (medium)

Path With Given Sequence (medium)

Count Paths for a Sum (medium)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

10. Pattern: Two Heaps

Introduction

Find the Median of a Number Stream (medium)

Sliding Window Median (hard)

Maximize Capital (hard)

Problem Challenge 1

Solution Review: Problem Challenge 1

11. Pattern: Subsets

Introduction

Subsets (easy)

Subsets With Duplicates (easy)

Permutations (medium)

String Permutations by changing case (medium)

Balanced Parentheses (hard)

Unique Generalized Abbreviations (hard)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

Problem Challenge 3

Solution Review: Problem Challenge 3

12. Pattern: Modified Binary Search

Introduction

Order-agnostic Binary Search (easy)

Ceiling of a Number (medium)

Next Letter (medium)

Number Range (medium)

Search in a Sorted Infinite Array (medium)

Minimum Difference Element (medium)

Bitonic Array Maximum (easy)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

Problem Challenge 3

Solution Review: Problem Challenge 3

13. Pattern: Bitwise XOR

Introduction

Single Number (easy)

Two Single Numbers (medium)

Complement of Base 10 Number (medium)

Problem Challenge 1

Solution Review: Problem Challenge 1

14. Pattern: Top 'K' Elements

Introduction

Top 'K' Numbers (easy)

Kth Smallest Number (easy)

'K' Closest Points to the Origin (easy)

Connect Ropes (easy)

Top 'K' Frequent Numbers (medium)

Frequency Sort (medium)

Kth Largest Number in a Stream (medium)

'K' Closest Numbers (medium)

Maximum Distinct Elements (medium)

Sum of Elements (medium)

Rearrange String (hard)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

Problem Challenge 3

Solution Review: Problem Challenge 3

15. Pattern: K-way merge

Introduction

Merge K Sorted Lists (medium)

Kth Smallest Number in M Sorted Lists (Medium)

Kth Smallest Number in a Sorted Matrix (Hard)

Smallest Number Range (Hard)

Problem Challenge 1

Solution Review: Problem Challenge 1

16. Pattern : 0/1 Knapsack (Dynamic Programming)

Introduction

0/1 Knapsack (medium)

Equal Subset Sum Partition (medium)

Subset Sum (medium)

Minimum Subset Sum Difference (hard)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

17. Pattern: Topological Sort (Graph)

Introduction

Topological Sort (medium)

Tasks Scheduling (medium)

Tasks Scheduling Order (medium)

All Tasks Scheduling Orders (hard)

Alien Dictionary (hard)

Problem Challenge 1

Solution Review: Problem Challenge 1

Problem Challenge 2

Solution Review: Problem Challenge 2

18. Miscellaneous

Kth Smallest Number (hard)

19. Conclusions

Where to Go from Here