Basic Calculator using Switch() loop

When Anyone introduce to programming .He wants to make something productive . And calculator is easiest thing which you can make from your very basic programming . And today we gonna Do this ...

We are going to make first Calculator program in C .

It can do following operation addition, subtraction, Division, Multiplication and Power .
these are very basic operation
steps :


    Including stranded header file stdio.h, Math.h , and stdlib.h .
   declare variables
  Now we make while loop with 1 as argument it means this loop gonna run infinite until we call break or exit   function . We use this to use program for many times until we want to stop .
  Now take variable a and b as input on which we have to do operation .
  than we have to enter Our choice of operation .depend on that switch loop choose operation .
  when we choose operation for sum it goes to case 1
  when we choose to exit it goes to case 6 to exit and program stop & Exit .

 If someone choose a option other than these operation it goes to default i.e  print wrong choice!

C code :

 // http://beginer2cs.blogspot.com  
 #include <stdio.h>  
 #include<math.h>  
 #include<stdlib.h>  
 void main ()  
 {  
      int index;  
      float a,b,c;  
      printf("Calculator.. ");  
      while(1)  
      {  
      printf("\nEnter two operands.. \n");  
      scanf("%f%f",&a,&b);  
      printf("\nMenu.. \n1. Addition \n2. Substraction \n3. Multiplication \n4. Division \n5 power \n6 to EXIT \n ");  
      printf("\n Enter choice : ");  
      scanf("%d",&index);  
      switch (index)  
      {  
           case 1:  
           c=a+b;  
           printf(" sum =%f",c);  
           break;  
           case 2:  
           c=a-b;  
           printf("Sub =%f",c);  
           break;  
           case 3:  
           c=a*b;  
           printf("multi =%f",a,b,c);  
           break;  
           case 4:  
           c=a/b;  
           printf("Div =%f",c);  
           break;  
           case 5:  
                printf("Pow = %f",pow(a,b));  
                break;  
           default:  
           case 6:  
                exit(0);  
                break;  
           printf("Wrong Choice");  
        }  
   }  
 }  

Have A nice DAY