While statement

The simplest of all the looping structures in is the while statement.
The basic format of while statement is
   while (test condition)
{
   body of the loop
}


include<stdio.h>
   void main( )
{
   int sum = 0;
   int n = 1;
   while (n<=10)
   {
   sum = sum + n*n;
   n = n+1;
   }
   print f ("sum = %d/n" ; sum);
}


Do-while
The general form of do while loop:
initialization:
   do{
        statement
        increment
       } while (condition);


include<stdio.h>
include<conio.h>
   void main( )
 {
   int i = 5;
   do { print f ("value of i = %d ", i);
   i++
   } while (i<5);
   print f ("/n current value of i =%d" , i);
   getch ( )
}