ID	Title	Difficulty
74	Search a 2D Matrix	Medium
75	Sort Colors	Medium
78	Subsets	Medium
79	Word Search	Medium
80	Remove Duplicates from Sorted Array II	Medium
81	Search in Rotated Sorted Array II	Medium
84	Largest Rectangle in Histogram	Hard
85	Maximal Rectangle	Hard
88	Merge Sorted Array	Easy
90	Subsets II	Medium
105	Construct Binary Tree from Preorder and Inorder Traversal	Medium
106	Construct Binary Tree from Inorder and Postorder Traversal	Medium
118	Pascal's Triangle	Easy
119	Pascal's Triangle II	Easy
120	Triangle	Medium
121	Best Time to Buy and Sell Stock	Easy
122	Best Time to Buy and Sell Stock II	Easy
123	Best Time to Buy and Sell Stock III	Hard
126	Word Ladder II	Hard
128	Longest Consecutive Sequence	Hard
152	Maximum Product Subarray	Medium
153	Find Minimum in Rotated Sorted Array	Medium
154	Find Minimum in Rotated Sorted Array II	Hard
162	Find Peak Element	Medium
167	Two Sum II - Input array is sorted	Easy
169	Majority Element	Easy
209	Minimum Size Subarray Sum	Medium
213	House Robber II	Medium
219	Contains Duplicate II	Easy
228	Summary Ranges	Easy