Variables

In order for Computer Processor to read what we type on the keyboard and display it on the computer screen, the processor need a memory called variables to store the character that we type and display it on the computer screen.

For example:
 
int p;
This line of C code means, "I want to create a space called p that is able to hold a variable of type integer." A variable has a name (in this case, p) and a type (in this case, int, an integer). You can store a value in p by writing the ‘=’ operator (called assignment operator):
  
p = 5;

This mean p holding a value 5 in it now.
To make use of the value inside variable p, we can type something like:
   
printf("%d", p);
This mean value 5 will be displayed on the computer screen.
In C, there are several standard types for variables:
• int - integer (whole number) values e.g 1,10,40,30
• float - floating point values e.g 1.1,3.33,2.65
• char - single character values (such as "k" or "Q")

float p;
p=3.123   
printf("%f", p);


char p;
p=k   
printf("%c", p);


                    
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