#include

#include

int main(void)

{

float data1,data2;

char op;

char reply;

do{

printf("Please enter the expression:\n");

scanf("%f %c%f",&data1,&op,&data2);//%c前有一空格

switch(op)

{

case "+":printf("%f+%f=%f\n",data1,data2,data1+data2);break;

case "-":printf("%f-%f=%f\n",data1,data2,data1-data2);break;

case "*":printf("%f*%f=%f\n",data1,data2,data1*data2);break;

case "/":if(fabs(data2)

{

printf("Division by zero!\n");

}

else

{

printf("%f/%f=%f\n",data1,data2,data1/data2);

}

break;

default:printf("Unknown operator!\n");

}

printf("Do you want to continue(Y/N or y/n?)");

scanf(" %c",&reply);//%c前有一空格

}

while(reply=="Y"||reply=="y");

printf("Program is over!\n");

return 0;

}

注意一定要有空格，否則程式無法正常執行