This becomes just as simple in one-based indexing if you take the negative view and have division round up and modulo run from (-n + 1) to 0 instead of 0..(n -

This becomes just as simple in one-based indexing if you take the negative view and have division round up and modulo run from (-n + 1) to 0 instead of 0..(n - 1). So you get "arr2d[i / width + 1][i % width] = array[i]" if your language does the logical thing with non-positive indexes. Using modular arithmetic to argue for zero-based indexing is close to circular reasoning.