Question

2) Write an elementary calculator in which the main program reads an integer input, an operation (+,-,*,/), and another integer input. It then passes this information to a function (calc) to perform this operation. This function (calc) returns the result using switch statements for operation decision. The program stops when the user inputs 0 for both integer inputs in the main program.

Answer 1

#include<stdio.h>
int main()
{
   int first,second,operator,ans;
   while(1)
   {
       printf("1.+\n2.-\n3.*\n4./\n");//this is line is written to display the available operation in the program.
       printf("Enter first number:");
       scanf("%d",&first);
       printf("Enter second number:");
       scanf("%d",&second);

//this condition is for terminate the loop if user enters to inputs 0
       if(first==0 && second==0)
       {
           break;
       }
       printf("Enter select the operation:");
       scanf("%d",&operator);
       ans=cal(first,second,operator);
       printf("%d\n\n",ans);
   }
}
int cal(int a,int b,int c)
{
   switch(c)
   {
       case 1:
           return a+b;
           break;
       case 2:
           return a-b;
           break;
       case 3:
           return a*b;
           break;
       case 4:
           return a/b;
           break;
   }
}

NOTE:

This only worked for integers.