/Cracking-The-Coding-Interview-Python-Solutions-and-Explanations

Cracking the Coding Interview in Python 3. The solutions all have detailed explanations with visuals.

Cracking the Coding Interview in Python - Solutions with Explanations

Detailed explanations to the coding interview questions in CTCI. The solutions are written in Python 3.

If you find this useful, a Github star would be much appreciated!! ⭐ ⭐ ⭐

Arrays and Strings

Problem Number Problem Name Status
1.1 Is Unique Read Solution ✅
1.2 Check Permutation Read Solution ✅
1.3 URLify Read Solution ✅
1.4 Palindrome Permutation Read Solution ✅
1.5 One Away Read Solution ✅
1.6 String Compression Read Solution ✅
1.7 Rotate Matrix Read Solution ✅
1.8 Zero Matrix Read Solution ✅
1.9 String Rotation Read Solution ✅

Linked Lists

Problem Number Problem Name Status
2.1 Remove Dups Read Solution ✅
2.2 Return Kth to Last Read Solution ✅
2.3 Delete Middle Node Read Solution ✅
2.4 Partition Read Solution ✅
2.5 Sum List Read Solution ✅
2.6 Palindrome Read Solution ✅
2.7 Intersection Read Solution ✅
2.8 Loop Detection Read Solution ✅

Stacks and Queues

Problem Number Problem Name Status
3.1 Three In One ❌
3.2 Stack Min ❌
3.3 Stack of Plates ❌
3.4 Queue via Stacks ❌
3.5 Sort Stack ❌
3.6 Animal Shelter ❌

Trees and Graphs

Problem Number Problem Name Status
4.1 Route Between Nodes ❌
4.2 Minimal Tree ❌
4.3 List of Depths ❌
4.4 Check Balanced ❌
4.5 Validate BST ❌
4.6 Successor ❌
4.7 Build Order ❌
4.8 First Common Ancestor ❌
4.9 BST Sequence ❌
4.10 Check Subtree ❌
4.11 Random Node ❌
4.12 Paths with Sum ❌

Bit Manipulation

Problem Number Problem Name Status
5.1 Insertion ❌
5.2 Binary to String ❌
5.3 Flip Bit to Win ❌
5.4 Next Number ❌
5.5 Debugger ❌
5.6 Conversion ❌
5.7 Pairwise Swap ❌
5.8 Draw Line ❌

Object Oriented Design

Problem Number Problem Name Status
7.1 Deck of Cards ❌
7.2 Call Center ❌
7.3 Jukebox ❌
7.4 Parking Lot ❌
7.5 Online Book Reader ❌
7.6 Jigsaw ❌
7.7 Chat Server ❌
7.8 Othello ❌
7.9 Circular Array ❌

Recursion and Dynamic Programming

Problem Number Problem Name Status
8.1 Triple Step ❌
8.2 Robot in a Grid ❌
8.3 Magic Index ❌
8.4 Power Set ❌
8.5 Recursive Multiply ❌
8.6 Towers of Hanoi ❌
8.7 Permutation without Dups ❌
8.8 Permutation with Dups ❌
8.9 Parens ❌
8.10 Paint Fill ❌
8.11 Coins ❌
8.12 Eight Queens ❌
8.13 Stack of Boxes ❌
8.14 Boolean Evaluation ❌

Sorting and Searching

Problem Number Problem Name Status
10.1 Sorted Merge ❌
10.2 Group Anagram ❌
10.3 Search in Rotated Array ❌
10.4 Sorted Search, No Size ❌
10.5 Sparse Search ❌
10.6 Sort Big File ❌
10.7 Missing Int ❌
10.8 Find Duplicates ❌
10.9 Sorted Matrix Search ❌
10.10 Rank from Stream ❌
10.11 Peaks and Valleys ❌

Moderate

Problem Number Problem Name Status
16.1 Number Swapper ❌
16.2 Word Frequencies ❌
16.3 Intersection ❌
16.4 Tic Tac Win ❌
16.5 Factorial Zeros ❌
16.6 Smallest Difference ❌
16.7 Number Max ❌
16.8 English Int ❌
16.9 Operations ❌
16.10 Living People ❌
16.11 Diving Board ❌
16.12 XML Encoding ❌
16.13 Bisect Squares ❌
16.14 Best Line ❌
16.15 Master Mind ❌
16.16 Sub Sort ❌
16.17 Contiguous Sequence ❌
16.18 Pattern Matching ❌
16.19 Pond Sizes ❌
16.20 T9 ❌
16.21 Sum Swap ❌
16.22 Langton's Ant ❌
16.23 Rand7 from Rand5 ❌
16.24 Pairs with Sum ❌
16.25 LRU Cache ❌
16.26 Calculator ❌

Hard

Problem Number Problem Name Status
17.1 Add Without Plus ❌
17.2 Shuffle ❌
17.3 Random Set ❌
17.4 Missing Number ❌
17.5 Letters and Numbers ❌
17.6 Count of 2s ❌
17.7 Baby Names ❌
17.8 Circus Tower ❌
17.9 Kth Multiple ❌
17.10 Majority Element ❌
17.11 Word Distance ❌
17.12 BiNode ❌
17.13 Re-Space ❌
17.14 Smallest K ❌
17.15 Longest Word ❌
17.16 The Masseuse ❌
17.17 Multi Search ❌
17.18 Shortest Supersequence ❌
17.19 Missing Two ❌
17.20 Continuous Median ❌
17.21 Volume of Histogram ❌
17.22 Word Transformer ❌
17.23 Max Black Square ❌
17.24 Max Submatrix ❌
17.25 Word Rectangle ❌
17.26 Sparse Similarity ❌

If you find this useful, a Github star would be much appreciated!! ⭐ ⭐ ⭐

Contributing

Pull requests are welcome. For major changes, please open an issue to discuss what you want to change.