385. Mini Parser

Given a nested list of integers represented as a string, implement a parser to deserialize it.

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221. Maximal Square

Given a 2D binary matrix filled with 0’s and 1’s, find the largest square containing only 1’s and return its area.

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212. Word Search II

Given a 2D board and a list of words from the dictionary, find all words in the board.

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79. Word Search

Given a 2D board and a word, find if the word exists in the grid.

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336. Palindrome Pairs

Given a list of unique words. Find all pairs of distinct indices (i, j) in the given list, so that the concatenation of the two words, i.e. words[i] + words[j] is a palindrome.

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220. Contains Duplicate III

Given an array of integers, find out whether there are two distinct indices i and j in the array such that the difference between nums[i] and nums[j] is at most t and the difference between i and j is at most k.

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246. Strobogrammatic Number

A strobogrammatic number is a number that looks the same when rotated 180 degrees (looked at upside down).

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361. Bomb Enemy

Given a 2D grid, each cell is either a wall ‘W’, an enemy ‘E’ or empty ‘0’ (the number zero), return the maximum enemies you can kill using one bomb.
The bomb kills all the enemies in the same row and column from the planted point until it hits the wall since the wall is too strong to be destroyed.
Note that you can only put the bomb at an empty cell.

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159. Longest Substring With at Most Two Distinct Characters

Given a string, find the length of the longest substring T that contains at most 2 distinct characters.

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340.Longest Substring With at Most K Distinct Characters

Given a string, find the length of the longest substring T that contains at most k distinct characters.

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17. Letter Combinations of a Phone Number

Given a digit string, return all possible letter combinations that the number could represent.

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43. Multiply Strings

Given two numbers represented as strings, return multiplication of the numbers as a string.

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022. Generate Parentheses

Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses.

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253.Meeting Rooms II

Given an array of meeting time intervals consisting of start and end times [[s1,e1],[s2,e2],…] (si < ei), find the minimum number of conference rooms required.

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108.Convert Sorted Array to Binary Search Tree

Given an array where elements are sorted in ascending order, convert it to a height balanced BST.

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