用java计算器代码下载 java做简单计算器的代码

package com.wyj.method;

import java.util.Scanner;

public class calculator {
    public static void main(String[] args) {
        System.out.println("请输入第一个数：");
        Scanner a = new Scanner(System.in);
        double num1 = a.nextDouble();
        System.out.println("请输入第二个数：");
        Scanner b = new Scanner(System.in);
        double num2 = b.nextDouble();
        System.out.println("请输入运算符：");
        Scanner f = new Scanner(System.in);
        String deal = f.next();
        switch (deal){
            case "+":
                System.out.println(add(num1,num2));
                break;
            case "-":
                System.out.println(sub(num1,num2));
                break;
            case "*":
                System.out.println(mult(num1,num2));
                break;
            case "/":
                System.out.println(div(num1,num2));
                break;
                default:
                    System.out.println("错误！");
        }


        a.close();
        b.close();
        f.close();
    }
    //加法
    public static double add(double a,double b){
        return a+b;
    }
    //减法
    public static double sub(double a,double b){
        return a-b;
    }
    //乘法
    public static double mult(double a,double b){
        return a*b;
    }
    //除法
    public static double div(double a,double b){
        return a/b;
    }
}