Teach Yourself Borland C++ in 14 Days - portal

Getting Your Feet Wet
There is a shortcut method to declaring and filling an array all at one time. It looks like this:
int myArray[5] = { -200, -100, 0, 100, 200 };
To take this one step further, if you know exactly how many elements your array will have,
and if you fill the array when you declare it, you can even leave out the array size when you
declare the array. In that case you would use the following:
int myArray[] = { -200, -100, 0, 100, 200 };
This works because the compiler can figure out from the list of values being assigned how
many elements are in the array and how much memory to allocate for the array.
Arrays can be multidimensional. To create a two-dimensional array of integers, you would
use code like this:
int mdArray[3][5];
This allocates storage for 15 ints (a total of 60 bytes, if you’re keeping score). You access
elements of the array like you do a simple array, with the obvious difference that you must
supply two subscript operators:
int x = mdArray[1][1] + mdArray[2][1];
Figure 1.8 illustrates how a two-dimensional array might look in memory.
Figure 1.8.
A two-dimensional
array in memory.
WARNING
Array[0][]
Array[1][]
Array[2][]
myArray[][0] myArray[][1] myArray[][2] myArray[][3] myArray[][4]
baseAddr baseAddr+4 baseAddr+8 baseAddr+12 baseAddr+16
baseAddr+20 baseAddr+24 baseAddr+28 baseAddr+32 baseAddr+36
baseAddr+40 baseAddr+44 baseAddr+48 baseAddr+52 baseAddr+56
You must be careful not to overwrite the end of an array. One powerful
feature of C++ is direct access to memory. Because of this feature, C++
will not prevent you from writing to a particular memory location even
if that location is memory your program isn’t supposed to have access
to. The following code is legal, but will result in a crash in your
program (or in Windows):
int array[5];
array[5] = 10;
This is a common error to make because you might think the last
element of this array is 5 when it is really 4. If you overwrite the end of
an array, you have no idea what memory you are overwriting. The
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