programming-for-dummies

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Using an Array
zero-based arrays, such as Visual Basic and REALbasic. One-based arrays are
less common, but found in some versions of BASIC along with less popular
languages like Pascal and Smalltalk.
When defining arrays, always make sure you know whether your programming
language creates zero-based or one-based arrays. Otherwise, you may
try to store data in non-existent array elements.
Definable bounds
To avoid confusion, some programming languages (such as Pascal) let you
define both the lower and upper bound arrays.
If you wanted to create an array to hold five integers, you could use the following
code:
Var
LotteryNumbers[1..5] of Integer;
This would number the LotteryNumbers array from 1 to 5. However, you
could choose any number range of five like this:
Var
LotteryNumbers[33..37] of Integer;
This would create an array of five elements, numbered from 33 to 37, as
shown in Figure 1-4.
Figure 1-4:
Some
programming
languages
let you
define the
numbering
of an array.
Var
LotteryNumbers[33..37] of Integer;
33 34 35 36 37
One advantage of defining the numbering of an array is that you can use
meaningful numbers. For example, if you wanted to store the names of
employees in an array, you could number the array so each array element is
identified by an employee number. So if Jan Howards has employee ID
number 102, Mike Edwards has employee ID number 103, and John