Initializing A Multi-Dimensional Array

A question that often arises when dealing with arrays that have more than one subscript is: "In what order are the array's elements stored?" For example, suppose we initialize a 3-dimensional array as follows:

       Int array[4][3][2]={0,1,2,3,4,5,6,7, ... etc.}

Into which elements of the array do each of the values (0-23) go? Well, one sure way to find out is to try it for ourselves and see what happens:

      Int array[4][3][2]={ 0, 1, 2, 3, 4, 5, \
                           6, 7, 8, 9,10,11, \
                          12,13,14,15,16,17, \
                          18,19,20,21,22,23}
      Do i=0,3
         Do j=0,2
            Do k=0,1
               output (array[i][j][k], 1)
            Loop
         Loop
      Loop

When we run the program, it displays:

    0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23

In other words, we see that:

0 was stored into array[0][0][0] 1 was stored into array[0][0][1] 2 was stored into array[0][1][0] 3 was stored into array[0][1][1] 4 was stored into array[0][2][0] 5 was stored into array[0][2][1] 6 was stored into array[1][0][0] 7 was stored into array[1][0][1] 8 was stored into array[1][1][0] --- etc. ---

From this, we can infer the general rule:

When storing data values into consecutive elements of an array,
the right-most subscript is the one that changes the fastest.

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