Variables
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Variable Type Description
Size in Bytes
Range from
Range to
char Character
1
-128
127
unsigned char Unsigned Character
1
0
255
short Short Integer
2
-32, 768
32,767
unsigned short Unsigned Short Integer
2
0
65,535

int

long

Integer

Long Integer

4
-2,147,483,648
2,147,483,647

unsigned int

unsigned long

Unsigned Integer

Unsigned Long Integer

4
0
4,294,967,296
float Floating Point (Real)
4

-3.4E308

-3.4 x 10^308

3.4E38

-3.4 x 10^308

double Double Floating Point (Real)
8

-1.7E308

-1.7 x 10^308

1.8E308

1.8 x 10^308

bool Boolean (true or false)
1
false
true

Upper and Lower-Case Variable Names
By convention, if you declare and define a variable, you should give it a name beginning with a lower-case letter.


Variable Arrays

A variable may hold a single value like: myAge
A one-dimensional list of the ages of 25 students in this class: studentAge[25] with indices ranging from 0 to 24.
A two-dimensional table of the position of pieces on a chess board: chessGame[8][8] with indices ranging from 0 to 7.
Indices are always set off by square brackets [] and we always begin counting index values at zero.

Variable Scope