• Cracking the Coding Interview
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Cracking the Coding Interview

Section	Question	Solution	Difficulty	Great Problem
1.1	Is Unique	Solution	Easy	*
1.2	Check Permutations	Solution	Easy
1.3	URLify	Solution	Easy	*
1.4	Palindrome Permutation	Solution	Easy	*
1.5	One Away	Solution	Medium	*
1.7	Rotate Matrix	Solution	Hard	*
1.8	Zero Matrix	Solution	Easy	*
1.9	String Rotation	Solution	Easy
2 - Intro	Implement a List	Solution	Easy	*
2.1	Remove Dups	Solution	Easy	*
2.2	Return Kth to Last	Solution	Easy
2.3	Delete Middle Node	Solution	Easy
2.4	Partition	Solution	Medium	*
2.5	Sum Lists	Solution	Medium
2.6	Palindrome	Solution	Medium	*
2.7	Intersection	Solution	Medium	*
2.8	Loop Detection	Solution	Hard	*
3 - Intro	Implement a Stack	Solution	Easy	*
3 - Intro	Implement a Queue	Solution	Easy	*
3.1	Three in One	Solution	Medium
3.2	Stack Min	Solution	Medium	*
3.4	Queue via Stacks	Solution	Medium	*
3.5	Sort Stack	Solution	Medium	*
4 - Intro	Implement a TreeNode	Solution	Easy	*
4 - Intro	Pre-In-Post order Traversals	Solution	Easy	*
4 - Intro	Implement a GraphNode	Solution	Easy	*
4 - Intro	Breadth-First Search (BFS)	Solution	Medium	*
4 - Intro	Depth-First Search (DFS)	Solution	Medium	*
4 - Intro	Bidirectional Search	Solution	Easy	*
4.01	Route Between Nodes	Solution	Easy	*
4.02	Minimal Tree	Solution	Medium	*
4.03	List of Depths	Solution	Medium	*
4.04	Check Balanced	Solution	Medium	*
4.05	Validate BST	Solution	Medium	*
4.06	Successor	Solution	Medium	*
4.07	Build Order	Solution	Hard	*
4.08	First Common Ancestor	Solution	Hard	*
4.09	BST Sequences	Solution	Hard
4.10	Check Subtree	Solution	Medium
4.11	Random Node	Solution	Hard	*
4.12	Paths with Sum	Solution	Hard	*
5 - Intro	BitFunctions: getBit	Solution	Easy
5 - Intro	BitFunctions: setBit	Solution	Easy
5 - Intro	BitFunctions: clearBit	Solution	Easy
5.2	Binary to String	Solution	Medium
5.3	Flip Bit to Win	Solution	Medium
5.4	Next Number	Solution	Hard
5.6	Conversion	Solution	Easy
5.7	Pairwise Swap	Solution	Medium
6 - Intro	Prime - isPrime	Solution	Easy
6 - Intro	Prime - generate Primes	Solution	Medium
7.12	Hash Table	Solution	Hard	*
8 - Intro	Fibonacci	Solution	Easy	*
8.01	Triple Step	Solution	Easy	*
8.02	Robot in a Grid	Solution	Hard
8.03	Magic Index	Solution	Medium	*
8.04	Power Set	Solution	Hard	*
8.05	Recursive Multiply	Solution	Medium	*
8.06	Towers of Hanoi	Solution	Hard	*
8.08	Permutations with Dups	Solution	Hard	*
8.09	Parens	Solution	Medium	*
8.11	Coins	Solution	Hard	*
8.12	Eight Queens	Solution	Hard	*
8.13	Stack of Boxes	Solution	Hard	*
9 - Intro	4 Ways to Divide Data	Solution	Medium	*
9 - Intro	Find Words in Millions of Documents	Solution	Easy	*
9.4	Duplicate URLs	Solution	Medium	*
9.5	Cache	Solution	Medium	*
10 - Intro	Binary Search	Solution	Easy	*
10 - Intro	Merge Sort	Solution	Hard	*
10 - Intro	Quick Sort	Solution	Hard	*
10.01	Sorted Merge	Solution	Easy
10.02	Group Anagrams	Solution	Medium	*
10.03	Search in Rotated Array	Solution	Medium	*
10.04	Sorted Search No Size	Solution	Medium	*
10.06	Sort Big File	Solution	Medium	*
10.07	Missing Int	Solution	Hard
10.08	Find Duplicates	Solution	Easy	*
10.09	Sorted Matrix Search	Solution	Medium	*
10.10	Rank from Stream	Solution	Hard	*
10.11	Peaks and Valleys	Solution	Easy	*
Book Intro	Math cubes	Solution	Medium	*
7.09	Circular Array	Solution	Medium	*
13.5	TreeMap, HashMap, LinkedHashMap	Solution	Easy	*
15.1	Thread vs. Process	Solution	Medium
15.4	Deadlock-Free Class	Solution	Medium
15.5	Call in Order	Solution	Medium
15.6	Synchronized Methods	Solution	Easy
16.01	Number Swapper	Solution	Medium
16.04	Tic Tac Win	Solution	Medium	*
16.05	Factorial Zeros	Solution	Medium	*
16.06	Smallest Difference	Solution	Medium	*
16.08	English Int	Solution	Medium	*
16.10	Living People	Solution	Medium	*
16.11	Diving Board	Solution	Easy	*
16.14	Best Line	Solution	Hard	*
16.15	Master Mind	Solution	Medium
16.16	Sub Sort	Solution	Medium	*
16.17	Contiguous Sequence	Solution	Medium	*
16.18	Pattern Matching	Solution	Hard	*
16.19	Pond Sizes	Solution	Medium	*
16.20	T9	Solution	Medium	*
16.21	Sum Swap	Solution	Medium	*
16.22	Langtons Ant	Solution	Easy	*
16.23	Rand7 from Rand5	Solution	Medium	*
16.24	Pairs with Sum	Solution	Medium	*
16.25	LRU Cache	Solution	Hard	*
17.01	Add Without Plus	Solution	Medium	*
17.02	Shuffle	Solution	Hard	*
17.03	Random Set	Solution	Hard	*
17.05	Letters and Numbers	Solution	Hard	*
17.07	Baby Names	Solution	Easy	*
17.09	Kth Multiple	Solution	Hard	*
17.10	Majority Element	Solution	Hard	*
17.11	Word Distance	Solution	Medium	*
17.12	BiNode	Solution	Hard	*
17.14	Smallest K	Solution	Medium	*
17.15	Longest Word	Solution	Hard	*
17.16	The Masseuse	Solution	Medium	*
17.18	Shortest Supersequence	Solution	Hard	*
17.19	Missing Two	Solution	Medium	*
17.20	Continous Median	Solution	Hard	*
17.21	Volume of Histogram	Solution	Medium	*
17.22	Word Transformer	Solution	Hard	*
17.23	Max Black Square	Solution	Hard	*
17.24	Max Submatrix	Solution	Hard	*

LeetCode

#	Question	Solution	Difficulty	Great Problem
15	3sum	Solution	Medium	*
16	3sum Closest	Solution	Medium	*
20	Valid Parentheses	Solution	Easy	*
21	Merge Two Sorted Lists	Solution	Easy	*
23	Merge k Sorted Lists	Solution	Hard	*
28	Implement strStr()	Solution	Easy	*
98	Validate Binary Search Tree	Solution	Medium	*
104	Maximum Depth of Binary Tree	Solution	Easy	*
136	Single Number	Solution	Easy	*
141	Linked List Cycle	Solution	Easy	*
143	Reorder List	Solution	Medium	*
151	Reverse Words in a String	Solution	Medium	*
162	Find Peak Element	Solution	Medium	*
189	Rotate Array	Solution	Easy	*
200	Number of Islands	Solution	Medium	*
206	Reverse Linked List	Solution	Easy	*
300	Longest Increasing Subsequence	Solution	Medium	*
347	Top K Frequent Elements	Solution	Medium	*
518	Coin Change 2	Solution	Medium	*
560	Subarray Sum Equals K	Solution	Medium	*
692	Top K Frequent Words	Solution	Medium	*
695	Max Area of Island	Solution	Medium	*
1013	Pairs of Songs With Total Durations Divisible by 60	Solution	Easy	*

LeetFree

#	Question	Solution	Difficulty	Great Problem
694	Number of Distinct Islands	Solution	Medium	*
711	Number of Distinct Islands II	Solution	Hard

HackerRank

Question	Solution	Difficulty	Great Problem
Linked List - Print in Reverse	Solution	Easy	*
Linked List - Get Node Value	Solution	Easy	*
Counting Sort	Solution	Medium	*
Reverse a Doubly Linked List	Solution	Medium	*
Tree - Level Order Traversal	Solution	Medium	*
Java 1D Array	Solution	Medium	*
Java Dequeue	Solution	Medium	*
Java Singleton	Solution	Medium	*
Contacts	Solution	Hard	*
Array Manipulation	Solution	Hard	*
Electronics Shop	Solution	Easy
Minimum Distances	Solution	Easy
Find Digits	Solution	Easy
Picking Numbers	Solution	Easy
Ransom Note	Solution	Easy
Sansa and XOR	Solution	Easy
Making Anagrams	Solution	Medium
Repeated String	Solution	Medium
Inserting a Node Into a Sorted Doubly Linked List	Solution	Medium
Super Reduced String	Solution	Medium
Caesar Cipher	Solution	Medium
Gemstones	Solution	Medium
Maximizing XOR	Solution	Medium
Sum vs XOR	Solution	Hard

More Questions

Question	Solution	Difficulty	Great Problem
Dijkstra's Algorithm	Solution	Hard