字元 <題目1：簡易計算機 (使用到字元)>

程式說明

Please input an expression like 100 + 3

Operators should be in {+, -, *, /, %}, others with end the program

>100 + 3

100 + 3 = 103.

>100 - 3

100 - 3 = 97.

>100 * 3

100 * 3 = 300.

>100 / 3

100 / 3 = 33.

>100 % 3

100 % 3 = 1.

>100 / 0

Wrong expression.

>100 , 0

Bye.



#include <stdio.h>

int main()

{

    printf("Please input an expression like 100 + 3 \n"

            "Operators should be in {+, -, *, /, %}, others with end the program\n");

    bool cont = true;

    do{

        int num1, num2;

        char op;

        printf(">");

        scanf(" %d %c %d" , &num1 , &op , &num2);

        switch (op)

        {

            case '+':

                printf("%d + %d = %d.\n", num1, num2, num1+num2);

                break;


        
            case '-':

                printf("%d - %d = %d.\n", num1, num2, num1-num2);

                break;


        
            case '*':

                printf("%d * %d = %d.\n", num1, num2, num1*num2);

                break;


        
            case '/':
        
            case '%':

                if (num2 == 0) printf("Wrong expression.\n");

                else if (op == '/')

                {

                    printf("%d / %d = %d.\n", num1, num2, num1/num2);

                }

                else

                {

                    printf("%d %% %d = %d.\n", num1, num2, num1%num2);

                }

                break;

            default:
        
            cont = 0 ;

        }

    }while (cont);

    printf("Bye.");

    return 0;

}