Skip to main content

Constants and Variables in C

 

Constants in C: Constants are the terms that can't be changed during the execution of a program.

Examples: Integer Constants: 0, 1, 2, 3, 4, 5, 6, 7 . . . . . . .
Floating Constants: 0.0, 0.1, 0.2, 0.3, -0.4, 0.5, 5.1546, 2.5465, -1.02545 . . . . . . . 
Character  Constants:  Character  constants  are  the  constant  which  use  single  quotation  around 
characters. For example: 'a', 'l', 'm', 'F' etc.

Variables in C: Variables are memory location in computer's memory to store data. To indicate the memory location, each variable should be given a unique name called identifier. Variable names are just  the  symbolic  representation  of  a  memory  location.  Examples  of  variable  name:  ABC,  var_no, var_123, Var123, Count etc.

Basic Data Types in C: 

Char: a single byte that can hold a character (‘a’, ’b’, ’c’, ’d’, ’e’ . . . . . . . ) 
Int: An Integer can hold 2 or 4 byte integers (0, 1, 2, 3, 4, 5, 6, 7 . . . . . . .)
Float: A float can hold 4 byte floating points (0.0, 0.1,0.2, 0.3, -0.4,0.5,5.1546, 2.5465, -1.02545 . . .)
Double: Double is same as float just the difference is it can hold up to 8 byte (0.0, 0.1, 0.2, 0.3, -0.4, 
0.5, 5.1546, 2.5465, -1.02545 . . . . . . .)

Rules for writing variable name in C:

The first letter of a variable should be a letter, Variable name can be made up of both uppercase and lowercase letters, digits and underscore (_) only.
Examples:


Declaration of Variable
#include <stdio.h>
void main(){
int a1, a2;
int a_1;
}
#include<stdio.h>
void main ( ){ 
char b_1;
double db;
}
#include<stdio.h>
void main(){
float a_1, b2, b3, b4;
char jvh;
}
a1, a2 and a_1 are declared as integer now they can store integers.
b_1 and db are declared as char and do uble respectively now b_1 can store characters(fonts) and db can store fractioned numbers.
Here a_1, b2, b3, b4 can store floating points and jvh can store charac


Initialization of Variable
#include<stdio.h>
void main ( ){
float b1 ;
b1 = 2.302;
double a;
a = 7.202;
}
#include<stdio.h>
void main ( ){ 
char b_1 ;
b_1 = ‘r’;
int a;
a = 7;
}
#include <stdio.h>
void main(){
int a1 = 5;
int b1;
b1 = 5;
 }
B1 and a are declared and initialized.
Here b_1 is stores / initialize r
And a store’s 7 ..
a1 is initialized during declaration and b1 firstly initialize then declare on second line.















Comments

Popular posts from this blog

Why should I learn Computer language (Programming)? And why C language good for beginners?

1. Software is the spirit  ( आत्मा )  of hardware . 2. Just by joining some hardware (Electronics  Components) we can’t make our  Computers, Laptops, Mobiles, Tablets, etc. so programming is essential to make this hardware functional. 3. Program instructs and controls the hardware and C is the very basic language to start. 1. By learning a computer language you'll able to build your own software, OS, Virus, Antivirus. For example, WhatsApp, Hike, Calculator,  Media  Player, Facebook, Twitter. 5. After learning the C language you'll be able to build your own computer applications. 6. C language Helps to learn more advanced languages like Java, Dot Net, MATLAB. because this all language depends upon C language. 7. It is good for starters because it is just like the English language and easy to understand.

Format Specifying in C

  Data Types Format Specify Char %c  or %s Int %d or %i Float %f Using of Variable # include <stdio.h> void main() { int a = 5, b = 7; int c = a+b+3; printf (“C= %d”, c); } # include <stdio.h> void main() { int a = 5, b = 7; printf (“SUM= %d”, a+b); } # include <stdio.h> void main() { char a1 = ‘s’, a2 = ‘g’; printf (“%s%c%s%s”,a1,a2,a2,a1); } O/p: C = 15 O/p: C = 15 O/p: sggs

New trends and advantages of C language.

1. You can program the ROBOTS and  Automatic Running Machines  using C language. click here for more information.  2. For building more advanced  software or  Games you need to  learn more advanced languages like  Visual  Basic,  .NET, JAVA, ANDROID programming which is based on C.  3. To build a website you need only HTML and you can make your own website but for making it more advance you need to learn more web designing languages like CSS, JavaScript, Ajax, PHP and this all languages are very easy to learn if you have some basic knowledge about C. 4. After learning C you will be able to make your own software like Calculator, Games, Embedded Softwares, Compilers.