Problem 43995. convert 2D array of ones and zeros to checkerboard array of [1,2] where the original array was ones and zero elsewhere
Given a 2D array of ones and zeros, generate an equivalent sized checkerboard array of ones and twos. The checkerboard pattern starts with 2:
[2,1,2,1,2; 1,2,1,2,1; 2,1,2,1,2];
Then set this checkerboard array to zero wherever the original was zero.