int?main()?{
double?a,?b,?d?=?0.0;
char?c;
while?(1)?{
printf("輸入壹個算式，如：1+2：");
scanf("%lf%c%lf",?&a,?&c,?&b);
int?f?=?1;
switch?(c)?{
case?'-':
d?=?a?-?b;
break;
case?'+':
d?=?a?+?b;
break;
case?'*':
d?=?a?*?b;
break;
case?'/':
d?=?a?/?b;
break;
default:
f?=?0;
printf("沒有這個運算符號！\n");
break;
}
if?(f?==?1)?{
printf("結果：%lf\n",?d);
}
}
return?0;
}