Calc.c

#include <stdio.h>

int main() {

  char op;

  double first, second;

  printf("Enter an operator (+, -, *, /): ");

  scanf("%c", &op);

  printf("Enter two operands: ");

  scanf("%lf %lf", &first, &second);

  switch (op) {

    case '+':

      printf("%.1lf + %.1lf = %.1lf", first, second, first + second);

      break;

    case '-':

      printf("%.1lf - %.1lf = %.1lf", first, second, first - second);

      break;

    case '*':

      printf("%.1lf * %.1lf = %.1lf", first, second, first * second);

      break;

    case '/':

      printf("%.1lf / %.1lf = %.1lf", first, second, first / second);

      break;

    // operator doesn't match any case constant

    default:

      printf("Error! operator is not correct");

  }

  return 0;

}