README.md

Practice-Coding-Questions

Personal Practice Set - Doing One a Day (sometimes) in a Variety of Languages (Mostly Python)!

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Leetcode

#	Difficulty	Problem	Solution
1	Easy	Two Sum	Java, Python, Ruby
2	Medium	Add Two Numbers	C
3	Medium	Longest Substring Without Repeating Characters	Python
4	Hard	Median of Two Sorted Arrays	Python
5	Medium	Longest Palindromic Substring	Python
6	Medium	Zig Zag Conversion	Java
7	Easy	Reverse Integer	Python
8	Medium	String to Integer	Ruby
9	Easy	Palindrome Number	C, Java, Python, Swift
10	Hard	Regular Expression Matching	Python
11	Medium	Container With Most Water	Python
12	Medium	Integer to Roman	Python
13	Easy	Roman to Integer	C, Python
14	Easy	Longest Common Prefix	Python
15	Medium	3Sum	Python
16	Medium	3Sum Closest	Python
17	Medium	Letter Combinations of a Phone Number	Python
18	Medium	4Sum	Python
19	Medium	Remove Nth Node From End of List	Python
20	Easy	Valid Parentheses	Java, Python
21	Easy	Merge Two Sorted Lists	Java, Python
22	Medium	Generate Parentheses	Python
23	Hard	Merge k Sorted Lists	Python
24	Medium	Swap Node in Pairs	Python
25	Hard	Reverse Nodes in k-Group	Python
26	Easy	Remove Duplicates from Sorted Array	C, Python
27	Easy	Remove Element	Python
28	Easy	Implement strStr()	C, Python
29	Medium	Divide Two Integers	Python
31	Medium	Next Permutation	Python
33	Medium	Search in Rotated Sorted Array	Python
34	Medium	Find First and Last Position of Element in Sorted Array	Python
35	Easy	Search Insert Position	Go, Java, JavaScript, Scala
36	Medium	Valid Sudoku	Python
38	Easy	Count and Say	Python
39	Medium	Combination Sum	Python
40	Medium	Combination Sum II	Python
42	Hard	Trapping Rain Water	Python
43	Medium	Multiply Strings	Python
44	Hard	Wildcard Matching	Python
46	Medium	Permutations	Python
47	Medium	Permutations II	Python
48	Medium	Rotate Image	Python
49	Medium	Group Anagrams	Python
50	Medium	Pow(x, n)	Python
53	Easy	Maximum Subarray	Java
54	Medium	Spiral Matrix	Python
55	Medium	Jump Game	Python
56	Medium	Merge Intervals	Python
58	Easy	Length of Last Word	Python
62	Medium	Unique Paths	Python
63	Medium	Unique Paths II	Python
64	Medium	Minimum Path Sum	Python
66	Easy	Plus One	Python
67	Easy	Add Binary	Python
69	Easy	Sqrt()	Python
70	Easy	Climbing Stairs	C
76	Hard	Minimum Window Substring	Python
78	Medium	Subsets	Python
79	Medium	Word Search	Python
83	Easy	Remove Duplicates from Sorted List	Python
84	Hard	Largest Rectangle in Histogram	Python
85	Hard	Maximal Rectangle	Python
88	Easy	Merge Sorted Array	Python
100	Easy	Same Tree	Python
101	Easy	Symmetric Tree	Python
102	Medium	Binary Tree Level Order Traversal	Python
104	Easy	Maximum Depth of Binary Tree	Python
105	Medium	Construct Binary Tree from Preorder and Inorder Traversal	Python
106	Medium	Construct Binary Tree from Inorder and Postorder Traversal	Python
107	Easy	Binary Tree Level Order Traversal II	Python
108	Easy	Convert Sorted Array to Binary Search Tree	Python
110	Easy	Balanced Binary Tree	Python
111	Easy	Minimum Depth of Binary Tree	Python
112	Easy	Path Sum	Python
118	Easy	Pascal's Triangle	Python
121	Easy	Best Time to Buy and Sell Stock	Python
122	Easy	Best Time to Buy and Sell Stock II	Python
123	Hard	Best Time to Buy and Sell Stock III	Python
125	Easy	Valid Palindrome	Python
127	Medium	Word Ladder	Python
133	Medium	Clone Graph	Python
136	Easy	Single Number	Python
137	Medium	Single Number II	Python
139	Medium	Word Break	Python
141	Easy	Linked List Cycle	Python
142	Medium	Linked List Cycle II	Python
146	Hard	LRU Cache	Python
148	Medium	Sort List	Python
153	Medium	Find Minimum in Rotated Sorted Array	Python
155	Easy	Min Stack	Python
162	Medium	Find Peak Element	Python
168	Easy	Excel Sheet Column Title	Python
171	Easy	Excel Sheet Column Number	Python
173	Medium	Binary Search Tree Iterator	Python
188	Hard	Best Time to Buy and Sell Stock IV	Python
191	Easy	Number of 1 Bits	Python
196	Easy	Delete Duplicate Emails	SQL
200	Medium	Number of Islands	Python
204	Easy	Count Primes	Python
206	Easy	Reverse Linked List	Python
207	Medium	Course Schedule	Python
208	Medium	Implement Trie	Java, Python
215	Medium	Kth Largest Element in an Array	Python
218	Hard	The Skyline Problem	Python
226	Easy	Invert Binary Tree	Python
231	Easy	Power Of Two	Python
234	Easy	Palindrome Linked List	Python
235	Easy	Lowest Common Ancestor of a Binary Search Tree	Python
236	Medium	Lowest Common Ancestor of a Binary Tree	Python
237	Easy	Delete Node in a Linked List	Python
238	Medium	Product of Array Except Self	Python
240	Medium	Search a 2D Matrix II	Python
258	Easy	Add Digits	Python
268	Easy	Missing Number	Python
273	Hard	Integer to English Words	Python
283	Easy	Move Zeroes	Python
287	Medium	Find the Duplicate Number	Python
295	Hard	Find Median from Data Stream	Python
297	Hard	Serialize and Deserialize Binary Tree	Java
301	Hard	Remove Invalid Parentheses	Python
310	Medium	Minimum Height Trees	Python
341	Medium	Flatten Nested List Iterator	Python
344	Easy	Reverse String	Python
388	Medium	Longest Absolute File Path	Python
389	Easy	Find the Difference	Python
461	Easy	Hamming Distance	Python
495	Medium	Teemo Attacking	Python
535	Medium	Encode and Decode TinyURL	Python
733	Easy	Flood Fill	Python
771	Easy	Jewels and Stones	Python
1114	Easy	Print in Order	Python

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SPOJ

#	Difficulty	Problem	Solution
1	Easy	Life, the Universe, and Everything	C
2
3

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Hackerrank

30 Days of Code Challenge

Day	Difficulty	Problem	Solution
0	Easy	Hello, World.	Java
1	Easy	Data Types	Java
2	Easy	Operators	Java
3	Easy	Conditional Statements	Python
4	Easy	Class vs Instance	Python
5	Easy	Loops	Python
6	Easy	Let's Review	Python
7	Easy	Arrays	Python
8	Easy	Dictionaries and Maps	Python
9	Easy	Recursion	Python
10	Easy	Binary Number	Python
11	Easy	2D Arrays	Python
12	Easy	Inheritance	Python
13	Easy	Abstract Classes	Python
14	Easy	Scope	Python
15	Easy	Linked List	Python
16	Easy	Exceptions - String to Integer	Python
17	Easy	More Exceptions	Python
18	Easy	Queues and Stacks	Python
19	Easy	Interfaces	Java
20	Easy	Sorting	Python
21	Easy	Generics	Java
22	Easy	Binary Search Trees	Java
23	Easy	BST Level-Order Traversal	Python
24	Easy	More Linked Lists	Python
25	Medium	Running Time and Complexity	Python
26	Easy	Nested Logic	Python
27	Easy	Testing	Python
28	Medium	RegEx, Patterns, and Intro to Databases	Python
29	Medium	Bitwise AND	Python

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CTCI

Cracking the Coding Interview 6th Edition Python Solutions

#	Difficulty	Problem	Solution
1.1		Is Unique	Python
1.2		Check Permutation	Python
1.3		URLify	Python
1.4		Palindrome Permutation	Python
1.5		One Away	Python
1.6		String Compression	Python
1.7		Rotate Matrix	Python
1.8		Zero Matrix	Python
1.9		String Rotation	Python
2.1		Remove Dups	Python
2.2		Return Kth to Last	Python
2.3		Delete Middle Node	Python
2.4		Partition	Python
2.5		Sum Lists	Python
2.6		Palindrome	Python
2.7		Intersection	Python
2.8		Loop Detection	Python
3.1		Three in One	Python
3.2		Stack Min	Python
3.3		Stack of Plates	Python
4.1		Route Between Nodes	Python
4.2		Minimal Tree	Python
4.3		List of Depths	Python
4.4		Check Balanced	Python
4.5		Validate BST	Python
4.6		Successor	Python
4.7		Build Order	Python
4.8		First Common Ancestor	Python
4.9		BST Sequences	Python
4.10		Check Subtree	Python
4.11		Random Node	Python
4.12		Paths With Sum	Python
5.1		Insertion	Coming Soon
8.1		Triple Step	Python
8.2		Robot in a Grid	Python
8.3		Magic Index	Python
8.4		Power Set	Python
8.5		Recursive Multiply	Python
8.6		Towers of Hanoi
8.7		Permutations Without Dups	Python
8.8		Permutations With Dups	Python
17.1		Add Without Plus	Python

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Google Foobar Challenge

#	Level	Problem	Solution
1	1	Solar Doomsday	Java
2	2	Gearing Up For Destruction	Python
3	2	Lovely Lucky Lambs	Python