#include <stdio.h>
int main(void)
{
    int op_1, op_2, result;
    unsigned char operator;
    printf("*********************************\n");
    printf("*   DER KLEINE TASCHENRECHNER   *\n");
    printf("*********************************\n\n\n");
    printf("Rechnung eingeben (z.b. 3+4)\n\n");
    printf("Zum Beenden etwas anderes eingeben\n");
    while(1)
    {
        if(scanf(" %d %c %d", &op_1,  &operator, &op_2)==3)
        {
            int error=0;
            switch(operator)
            {
                case '+':
                result=op_1+op_2;
                break;
                case '-':
                result=op_1-op_2;
                break;
                case '*':
                result=op_1*op_2;
                break;
                case '/':
                if(!op_2)
                {
                    printf("Division durch 0 :(");
                    error=1;
                }
                else
                {
                    result=op_1/op_2;
                }
                break;
                default:
                printf("Nur + - * /\n");
            }
            if(!error)
            {
                printf("%d %c %d = %d\n\n", op_1, operator, op_2, result);
            }
        }
        else
        {
            printf("Bye\n");
            return 0;
        }
    }
    return 0;
}