Variables in C Language

A variable is a name that may be used to store a data value.
Unlike constant, variables are changeable, we can change value of a variable during execution of a program.
A programmer can choose a meaningful variable name.
Example : average, height, age, total etc.

Rules to define variable name

• Variable name must be upto 8 characters.
• Variable name must not start with a digit.
• Variable name can consist of alphabets, digits and special symbols like underscore _.
• Blank or spaces are not allowed in variable name.
• Keywords are not allowed as variable name.

Declaration of variable

Declaration of variables must be done before they are used in the program. Declaration does two things.

• It tells the compiler what the variable name is.
• It specifies what type of data the variable will hold.

Example:

//Write a Program for Addition of two Numbers.
#include<stdio.h>
#include<conio.h>
void main()
{
    int a,b,sum;    //variable declaration
    a=30;
    b=20;
    sum=a+b;
    printf("Sum is %d",sum);
    getch();
}

Output:

---

• Prev
• Next

---

Questions

---

---

---

---