Question

Write a program that reads numbers from scanf¹ (keyboard) and then sums them, stopping when 0 has been entered. Construct three versions of this program, using the while, do-while, and for loops.

Answer 1

Code using for loop:

#include<stdio.h>
int main()
{
   int i,k=1,sum=0;
   for(i=0;k!=0;i++)
   {
       printf("Enter your input: ");
       scanf("%d",&k);
       sum=sum+k;
   }
   printf("%d",sum);
}

Indentation:

Output;

Code using while loop:

#include<stdio.h>
int main()
{
   int i,k=1,sum=0;
   while(k)
   {
       printf("Enter your number:");
       scanf("%d",&k);
       sum=sum+k;
   }
   printf("Sum is : %d", sum);
}

Indentation:

Output:

Code using do-while loop:

#include<stdio.h>
int main()
{
   int i,k,sum=0;
   do
   {
       printf("Enter your number:");
       scanf("%d",&k);
       sum=sum+k;
   }while(k);
   printf("Sum is : %d", sum);
}

Indentation:

Output: