简易计算器

• 思路推荐
  • 写4个方法：+、-、*、/
  • 利用循环+switch进行用户交互
  • 传递需要操作的2个数
  • 输出结果

package com.zhen.method;

import java.util.Scanner;

public class HomeWork {

    public static void main(String[] args) {
        double a = 0;
        double b = 0;
        Scanner scanner = new Scanner(System.in);

                System.out.println("请输入第一个数后按回车：");
                    a = scanner.nextDouble();

                System.out.println("请输入+、-、*、/后按回车");
                String method = scanner.next();

                System.out.println("请输入第二个数后按回车：");
                b = scanner.nextDouble();


        switch (method) {
            case "+":             //加法
                System.out.println(a + "+" + b +"="+ add(a,b));
                break;
            case "-":             //减法
                System.out.println(a + "-" + b +"="+ min(a,b));
                break;
            case "*":             //乘法
                System.out.println(a + "*" + b +"="+ mul(a,b));
                break;
            case "/":             //除法
                System.out.println(a + "/" + b +"=" + div(a,b));
                break;
            default:
                System.out.println("请输入正常算法！");

        }


        scanner.close();

        }



    //加法

    public static double add(double a,double b){
        return a+b;
    }

    //减法
    public static double min(double a,double b){
        return a-b;
    }

    //乘法
    public static double mul(double a,double b){
        return a*b;
    }

    //除法
    public static double div(double a,double b){
        return a/b;
    }

}