Programming Using C: Variables and printf

Last time we took a look at a simple program in C that used the printf function to output some string to the screen. Today, we will look further at printf and discuss other cool things that you can do with it.

A standard printf statement will look something like this:

printf(format-string, arguments);

A format-string can consists of three components: regular characters, control characters, and formats.

Regular Characters: Any letter or number.

Control Characters: (Note the new line character '\n' that we saw in the past tutorial)

\a      Write a <bell> character.

\b     Write a <backspace> character.

\c      Ignore remaining characters in this string.

\f      Write a <form-feed> character.

\n     Write a <new-line> character.

\r      Write a <carriage return> character.

\t      Write a <tab> character.

\v     Write a <vertical tab> character.

\'      Write a <single quote> character.

\\      Write a backslash character.

Formats: (A few basic ones are listed below)

%d      Decimal integer 

%c      Character

%s      String

%f       Floating Point

%lf      Double / Long Flaoting Poing

%p      Pointer

Review of Variables and their Declarations

A variable is a place holder for a value stored in memory on you computer. A standard declaration of a variable is as follows:

variable_type variable_name = variable_value;

As an example, we can declare an integer, named height, and assign it the value of 6:

int height = 6;

Note: You MUST declare a variable before you can use it!

Variable Types

char1 byte-128...127
short int 2 bytes -32,768...32,767 or, 
int 4 bytes -2,147,483,648...2,147,483,647
float 4 bytes 3.4E-38 ... 3.4E+38
double8 bytes 1.7E-308 ... 1.7E+308

Below are to simple programs, leave a comment below with the correct output of both programs:


#include <stdio.h>
int main(void) 
 return 0;


#include <stdio.h>
int main(void) 
 int length = 10;

 printf("The value stored in the length variable is: %d", length);
 return 0;

More tutorials coming soon! Let me know how you like the tutorials by commenting below and if there is any specific topics or languages you would like covered.

Programming in C: Defines and Includes

First C Program: Explained