C Format Specifiers
Format Specifiers
Format specifiers are used together with the printf()
function to tell the compiler what type of data the variable is storing. It is
basically a placeholder for the variable value.
A format specifier starts
with a percentage sign %
, followed by a character.
For example, to output the value of an int
variable,
use the format
specifier %d
surrounded by double quotes (""
),
inside the printf()
function:
To print other types, use %c
for char
and %f
for float
:
Example
// Create variables
int myNum = 15; // Integer (whole number)
float
myFloatNum = 5.99; // Floating point number
char myLetter = 'D'; //
Character
// Print variables
printf("%d\n", myNum);
printf("%f\n", myFloatNum);
printf("%c\n", myLetter);
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To combine both text and a variable, separate them with a comma inside the
printf()
function:
To print different types in a single printf()
function, you can use the
following:
Example
int myNum = 15;
char myLetter = 'D';
printf("My number is %d and my
letter is %c", myNum, myLetter);
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You will learn more about Data Types in a later chapter.
Print Values Without Variables
You can also just print a value without storing it in a variable, as long as you use the correct format specifier:
Example
printf("My favorite number is: %d", 15);
printf("My favorite letter is:
%c", 'D');
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However, it is more sustainable to use variables as they are saved for later and can be re-used whenever.