Pattern matching. Given an n-by-n subarray of black (1) and white (0) pixels, design a linear-time algorithm that finds the largest square subarray that contains no white pixels. In the following...

Pattern matching. Given an n-by-n subarray of black (1) and white (0) pixels, design a linear-time algorithm that finds the largest square subarray that contains no white pixels. In the following example, the largest such subarray is the 3-by-3 subarray highlighted in blue.

Implement your algorithm and confirm that the order of growth of its running time is linear in the number of pixels. Extra credit: Design an algorithm to find the largest rectangular black subarray.