Map array index to matrix

Question

My problem is this: I've an array with values from 0 to 8(a[9]=[0,1,2,....,8] and I would map the indexes of array to a matrix 3x3. This is useful for me to develop the "Broadcast Multiply Rolling" algorithm to make the product of two matrices. Thank to everyone

Answer 1

If index is an index into a single-dimensional array of 9 elements, the array can be viewed as a two-dimensional 3x3 array with this:

int row = index / 3;
int column = index % 3;
int foo = array[row][column];