实现两个数之间的加减乘除

import java.util.Scanner;
//实现两个数之间的四则运算
public class Demo03 {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);  //将scanner对象导入
        double result = 0;
        
        //分别输入计算的数字和符号
        System.out.print("请输入第一个数字");
        double num1 = scanner.nextDouble();

        System.out.print("请输入运算字符");
        String operate = scanner.next();

        System.out.print("请输入第二个数字");
        double num2 = scanner.nextDouble();

        //switch语句来判断计算符号
        switch (operate){
            case "+" :
                result = add(num1,num2);
                break;

            case "-" :
                result = sub(num1,num2);
                break;

            case "*" :
                result = mult(num1,num2);
                break;
            case "/" :
                result = div(num1,num2);
                break;
        }
        System.out.println(result);
    }


    //定义加、减、乘、除四个方法
    public static double add(double num1, double num2){
        return  num1 +num2;
    }

    public static double sub(double num1, double num2){
        return num1-num2;
    }

    public static double mult(double num1, double num2){
        return num1*num2;
    }

    public static double div(double num1, double num2){
        return num1/num2;
    }
}