Java实现计算器

package com.itheima;

import java.util.Scanner;

/*
    案例:黑马计算器
 */
public class Demo08 {
    public static void main(String[] args) {
        Scanner sc = new Scanner (System.in);
        System.out.println ("#欢迎使用黑马计算器");
        while (true) {
            System.out.println ("请选择您要使用的运算方式:[1.加法,2.减法,3.乘法,4.除法,5取余,0.退出]");
            int key = sc.nextInt ();
            switch (key) {
                case 1:
                    add ();
                    break;
                case 2:
                    jian ();
                    break;
                case 3:
                    cheng ();
                    break;
                case 4:
                    chu ();
                    break;
                case 5:
                    mo ();
                    break;
                case 0:
                    System.out.println ("谢谢使用黑马计算器,正在退出...");
                    System.exit (0);
                default:
                    System.out.println ("你选择的功能尚未开发");
                    break;
            }
        }
    }

    public static void add() {
        Scanner sc = new Scanner (System.in);
        System.out.println ("请输入第一个整数:");
        int a = sc.nextInt ();
        System.out.println ("请输入第二个整数:");
        int b = sc.nextInt ();
        int sum = a + b;
        System.out.println ("和: " + sum);
    }

    public static void jian() {
        Scanner sc = new Scanner (System.in);
        System.out.println ("请输入第一个整数:");
        int a = sc.nextInt ();
        System.out.println ("请输入第二个整数:");
        int b = sc.nextInt ();
        int cha = a - b;
        System.out.println ("差: " + cha);
    }

    public static void cheng() {
        Scanner sc = new Scanner (System.in);
        System.out.println ("请输入第一个整数:");
        int a = sc.nextInt ();
        System.out.println ("请输入第二个整数:");
        int b = sc.nextInt ();
        int ji = a * b;
        System.out.println ("积: " + ji);
    }

    public static void chu() {
        Scanner sc = new Scanner (System.in);
        System.out.println ("请输入第一个整数:");
        int a = sc.nextInt ();
        System.out.println ("请输入第二个整数:");
        int b = sc.nextInt ();
        int shang = a / b;
        System.out.println ("商: " + shang);
    }

    public static void mo() {
        Scanner sc = new Scanner (System.in);
        System.out.println ("请输入第一个整数:");
        int a = sc.nextInt ();
        System.out.println ("请输入第二个整数:");
        int b = sc.nextInt ();
        int yu = a + b;
        System.out.println (" 余数: " + yu);
    }
}