Problem - Kevin Tafuro

Figure 12-1. Memory representation of split arrays
Before merge
Before split
Figure 12-2. Memory representation of merged arrays
Folded arrays created using the spc_array_fold( ) function become multidimensional
arrays, similar to the two-dimensional arrays created with spc_array_split( ).
Each array element is referenced by an index as if it were in a single-dimensional
array. The number of dimensions chosen determines the ordering of the elements.
The memory representation of folded arrays is illustrated in Figure 12-3.
Figure 12-3. Memory representation of folded arrays
The spc_array_flat( ) function stores multiple arrays or a multidimensional array as
a single-dimensional array with each element referenced by an array number and an
index into that array. The first element of each array is stored, followed by the second
element of each array, and so forth until the end of the arrays are reached. Note
that not all arrays need be the same size for this to work correctly, as long as the
space reserved for the one-dimensional array contains NULL entries for the unused elements.
The memory representation of flat arrays is illustrated in Figure 12-4.
Figure 12-4. Memory representation of flat arrays
676 | Chapter 12: Anti-Tampering
A1 A2 A3 A4 A5 A6
A1 A2 A3 A4 A5 A6 A7
B1 B2 B3
Before fold
A1 A2 A3 A4 A5 A6 A7
Before flatten
A11 A12 A13 A 21 A 22 A 23
A 31 A 32 A 33
After merge
After split
A1 A3 A5
A2 A4 A6
A1 A2 B1 A3 A4 B2 A5 A6 B3 A7
After fold
A8 A1 A4 A7
A2 A5 A8
A3 A6
After flatten
A11 A21 A31 A12 A22 A32 A13 A23 This is the Title of the Book, eMatter Edition
Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.
A 33