Given a 2D binary matrix filled with 0's and 1's, find the largest square containing all 1's and return its area.
For example, given the following matrix:
Return 4.
解法很巧妙，我也是看了discuss，首先列出最左一列和最上面一列，剩下的解法可以看這個
Basic idea is to iterate over all columns and rows of a matrix (starting with i=j=1). If value in a cell>0 and cells to the north, west, and north-west are >0, pick smallest value of those 3 cells, take it's square root, add 1, and assign square of new value to current cell. For example given matrix
Our answer is the largest value in new matrix: 16
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* 本文來自部落格 “李博Garvin“
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