Question

Q2- Write a C program that work as a calculator for the 4 main operations ( + * / - ), an error message should be displayed when the user attempts to divide by zero.
The user input should be in this form:
Number operation number, ex: 2-3‏

Answer 1

/*
 *  C Program for a two input arithmetic calculator
 */

#include <stdio.h>

int main()
{
  int x,y;
  char c;
  printf("Enter two numbers and operator: ");
  scanf("%d %c %d", &x, &c, &y);

  switch(c)
  {
    case '+'  :
                printf("Result (%d %c %d): ", x, c, y);
                printf("%d\n", x+y);
                break;

    case '-'  :
                printf("Result (%d %c %d): ", x, c, y);
                printf("%d", x-y);
                break;

    case '*'  :
                printf("Result (%d %c %d): ", x, c, y);
                printf("%d", x*y);
                break;
    
    case '/'  :
                if (y)
                {
                  printf("Result (%d %c %d): ", x, c, y);
                  printf("%f", (float)x/y);
                }
                else
                  printf("Error: Divide by zero");
                break;

    default   :
                printf("Invalid Operation");
  }

  return 0;
}