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Arrays
Recall that an array is composed of a series of elements of one data type. You use
declarations to tell the compiler when you want an array. An array declaration tells the
compiler how many elements the array contains and what the type is for these elements.
Armed with this information, the compiler can set up the array properly. Array elements
can have the same types as ordinary variables. Consider the following example of array
declarations:
/* some array declarations */
int main(void)
{
float candy[365];
/* array of 365 floats */
char code[12];
/* array of 12 chars
*/
int states[50];
/* array of 50 ints
*/
...
}
The brackets (
[]
) identify
candy
and the rest as arrays, and the number enclosed in the
brackets indicates the number of elements in the array.
To access elements in an array, you identify an individual element by using its subscript
number, also called its index. The numbering starts with 0. Hence,
candy[0]
is the first
element of the
candy
array, and
candy[364]
is the 365th and last element.
This is rather old hat; let's learn something new.
Initialization
Arrays are often used to store data needed for a program. For example, a 12-element
array can store the number of days in each month. In cases such as these, it's convenient
to initialize the array at the beginning of a program. Let's see how it is done.
You know you can initialize single-valued variables (sometimes called scalar variables)
in a declaration with expressions such as
