Looping Statements in C

           A loop involves repeating some portion of the program either a specified number of times or until a condition is satisfied. This repetitive operation (loop) is achieved in C through a for, or while or do-while loop.

               The statements within the loop would keep getting executed till the condition being tested remains true. When the condition becomes false, the control is transferred to first statement that follows the body of the loop.

For loop:

Syntax:

for(initialization; testing; increment/decrement)

{

          //sequence of statements;

}

Example:

for(i=1;i<=5;i++)

{

          printf“\n%d”,i);

}

Program:

#include<stdio.h>

#include<conio.h>

void main()

{

          clrscr();

int i,factorial=1,n;

printf(“\nEnter the Number to find the factorial”);

scanf(“%d”,&n); //getting the input

for(i=1;i<=n;i++)

{

factorial=factorial*i;

}

printf(“\nThe factorial of %d is %d ”,n,factorial); //Displaying the output

getch();

}

Aim of this program is to find the factorial of the given number.

Program Explanation:

Include header files

Using scanf get the input to find the factorial.

Using for loop find the factorial of the given number.

Display the ouput.

While loop:

Syntax:

while(test_expression)

{

//sequence of statements;

}

Example:

while(i<5>

{

printf(“%d”,i);

i++;

}

Example Program:

#include<stdio.h>

#include<conio.h>

void main()

{

         

clrscr();

int i=1,factorial=1,n;

printf(“\nEnter the Number to find the factorial”);

scanf(“%d”,&n); //getting the input

while(i<=n)

{

factorial=factorial*i;

i++;

}

printf(“\nThe factorial of %d is %d ”,n,factorial); //Displaying the output

getch();

}