poteboy / LeetCode

Problem solving in algorithms & data structures

LeetCode

updating this repo with solutions to LeetCode problems on a daily basis for practice/modification purposes.

Database

#	Title	Language	Difficulty
175	Combine Two Tables	MySQL	Easy
181	Employees Earning More Than Their Managers	MySQL	Easy
183	Customers Who Never Order	MySQL	Easy
182	Duplicate Emails	MySQL	Easy
196	Delete Duplicate Emails	MySQL	Easy
595	Big Countries	MySQL	Easy
596	Classes More Than 5 Students	MySQL	Easy
620	Not Boring Movies	MySQL	Easy

Algorithms & Data Structures

#	Title	Topics	Difficulty
1	Two Sum	Hash Map	Easy
2	Add Two Numbers	Linked List	Medium
3	Longest Substring Without Repeating Characters	Sliding Window	Medium
4	Median of Two Sorted Arrays		Hard
7	Reverse Integer		Easy
9	Palindrome Number		Easy
19	Remove Nth Node From End of List	Linked List	Medium
20	Valid Parentheses	Stack	Easy
21	Merge 2 Sorted Lists	Linked List	Easy
23	Merge k Sorted Lists	Linked List	Hard
35	Search Insert Position	Binary Search	Easy
46	Permutations		Medium
47	Permutations II		Medium
50	Pow(x, n)		Medium
53	Maximum Subarray	Kadane's Algorithm	Easy
67	Add Binary	Bitwise Operation	Easy
75	Sort Colors	Sorting	Easy
78	Subsets		Medium
80	Remove Duplicates from Sorted Array II		Medium
81	Search in Rotated Sorted Array II		Medium
82	Remove Duplicates from Sorted List II	Linked List	Medium
83	Remove Duplicates from Sorted List	Linked List	Easy
94	Binary Tree Inorder Traversal	Binary Tree	Medium
100	Same Tree	Binary Tree	Easy
101	Symmetric Tree	Binary Tree	Easy
102	Binary Tree Level Order Traversal	Binary Tree	Medium
104	Maximum Depth of Binary Tree	Binary Tree	Easy
107	Binary Tree Level Order Traversal II	Binary Tree	Easy
109	Convert Sorted List to Binary Search Tree	Linked List, Binary Tree	Medium
111	Minimum Depth of Binary Tree	Binary Tree	Easy
112	Path Sum	Binary Tree	Easy
119	Pascal's Triangle II		Easy
118	Pascal's Triangle		Easy
125	Valid Palindrome		Easy
136	Single Number		Easy
141	Linked List Cycle	Linked List	Easy
142	Linked List Cycle II	Floyd's algorithm	Medium
144	Binary Tree Preorder Traversal	Binary Tree	Medium
145	Binary Tree Postorder Traversal	Binary Tree	Hard
147	Insertion Sort List	Linked List Sorting	Medium
148	Sort List	Linked List, Merge Sort	Medium
150	Evaluate Reverse Polish Notation		Medium
153	Find Minimum in Rotated Sorted Array	Binary Search	Medium
155	Min Stack	Stack	Easy
160	Intersection of Two Linked Lists	Linked List	Easy
167	Two Sum II	Hash Map	Easy
169	MajorityElement		Easy
173	Binary Search Tree Iterator	Binary Tree, Queue	Medium
189	Rotate Array		Easy
202	Happy Number	Recrursion	Easy
203	Remove Linked List Elements	Linked List	Easy
206	Reverse Linked List	Linked List	Easy
215	Kth Largest Element in an Array		Medium
222	Count Complete Tree Nodes	Binary Tree	Medium
225	Implement Stack using Queues	Stack	Easy
226	Invert Binary Tree	Binary Tree	Easy
231	Power of Two		Easy
232	Implement Queue using Stacks	Queue, Stack	Easy
235	Lowest Common Ancestor of a Binary Search Tree	Binary Tree	Easy
237	Delete Node in a Linked List	Linked List	Easy
258	Add Digits		Easy
263	Ugly Number		Easy
268	Missing Number	Math	Easy
287	Find the Duplicate Number	Math	Medium
326	Power of Three		Easy
342	Power of Four		Easy
344	Reverse String		Easy
374	Guess Number Higher or Lower	Binary Search	Easy
383	Ransom Note		Easy
384	Shuffle an Array		Medium
412	Fizz Buzz		Easy
442	Find All Duplicates in an Array		Medium
445	Add Two Numbers II	Linked List	Medium
476	Number Complement	Bitwise Operation	Easy
448	Find All Numbers Disappeared in an Array	Set Operation	Easy
485	Max Consecutive Ones		Easy
500	Keyboard Row	Set Operation	Easy
501	Find Mode in Binary Search Tree	Binary Tree	Easy
557	Reverse Words in a String III		Easy
617	Merge Two Binary Trees	Binary Tree	Easy
700	Search in a Binary Search Tree	Binary Tree	Easy
876	Middle of the Linked List	Linked List	Easy
1221	Split a String in Balanced Strings		Easy
1365	How Many Numbers Are Smaller Than the Current Number		Easy