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You are given an n x n 2D matrix representing an image.Rotate the image by 90 degrees (clockwise).Note:You have to rotate the image in-place, which me 阅读全文
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Given a string that contains only digits 0-9 and a target value, return all possibilities to add binary operators (not unary) +, -, or *between the di 阅读全文
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Given a set of words (without duplicates), find all word squares you can build from them.A sequence of words forms a valid word square if the kth row 阅读全文
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You are given a m x n 2D grid initialized with these three possible values.1. -1 - A wall or an obstacle.2. 0 - A gate.3. INF - Infinity means an empt 阅读全文
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Given a matrix consists of 0 and 1, find the distance of the nearest 0 for each cell.The distance between two adjacent cells is 1.Example 1: Input:0 0 阅读全文
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Given a 2D board containing 'X' and 'O' (the letter O), capture all regions surrounded by 'X'.A region is captured by flipping all 'O's into 'X's in t 阅读全文