C语言学习：用C语言实现简单的计算器

来源：cnblogs　　作者：大天使维迦　　时间：2021/3/8 11:58:03　　对本文有异议

用C语言编写一个简单的可以进行加减乘除运算混合运算的计算器的方法，利用运算符做为swich case 语句条件,实现简单程序的编写;并且对输入的运算做判断,除数为零也需做判断;

# include <stdio.h>
 
int main() {
char operator;
    double firstNumber,secondNumber;
    printf("输入操作符 (+, -, *,/): ");
    scanf("%c", &operator);
    printf("输入两个数字: ");
    scanf("%lf %lf",&firstNumber, &secondNumber);
    switch(operator)
{
case '+':
            printf("%.1lf + %.1lf = %.1lf",firstNumber, secondNumber, firstNumber + secondNumber);
            break;
        case '-':
            printf("%.1lf - %.1lf = %.1lf",firstNumber, secondNumber, firstNumber - secondNumber);
            break;
        case '*':
            printf("%.1lf * %.1lf = %.1lf",firstNumber, secondNumber, firstNumber * secondNumber);
            break;
        case '/':
            printf("%.1lf / %.1lf = %.1lf",firstNumber, secondNumber, firstNumber / secondNumber);
            break;
        // operator doesn't match any case constant (+, -, *, /)
 
default:
            printf("Error! operator is not correct");
    }
return 0;
}