JAVA理解逻辑程序的书上全部重要的习题

今天随便翻翻看以前学过JAVA理解逻辑程序的书上全部练习,为了一些刚学的学弟学妹,所以呢就把这些作为共享了.

希望对初学的学弟学妹有所帮助!

例子:升级“我行我素购物管理系统”，实现购物结算功能
代码：

public class OneDay {
    public static void main(String[] args) {
        int shirtPrice=245;
        int shoePrice=570;
        int pADpRICE=320;
        int ShoeNo=1;
        int shirtNo=2;
        int padNo=1;
        double discount=0.8;
        /*
         * 计算消费总金额
         * 
         * */
        double finalPay=(shirtPrice*shirtNo+        shoePrice*ShoeNo+shoePrice+pADpRICE*padNo)*discount;
        System.out.println("消费总金额："+finalPay);
    }
}

  
例子:升级“我行我素购物管理系统”，实现打印购物小票和计算积分功能
public class OneDay {
    public static void main(String[] args) {
        int shirtPrice=245;
        int shoePrice=570;
        int pADpRICE=320;
        int ShoeNo=1;
        int shirtNo=2;
        int padNo=1;
        double discount=0.8;
        double finalPay=(shirtPrice*shirtNo+shoePrice*ShoeNo+shoePrice+pADpRICE*padNo)*discount;
        double Sum=1800;
        double SuM=Sum-finalPay;
        //积分
        int Point=(int)finalPay*3/100;
    System.out.println("**********消费单***********");
    System.out.println("购买物品\t单价\t个数\t金额");
    System.out.println("T血\t￥245\t2\t￥490");
    System.out.println("网球鞋\t￥570\t1\t￥570");
    System.out.println("网球拍\t￥320\t1\t￥320\n");
    System.out.println("折扣：\t"+discount);
    System.out.println("消费总金额："+finalPay);
    System.out.println("实际交费\t￥"+Sum);
    System.out.println("找钱\t￥"+SuM);
    System.out.println("积分\t￥"+Point);
    }
}
  
//我行我素,幸运抽奖
public class OneDay {
    public static void main(String[] args) {
        int cusNO;//客户会员号
        System.out.println("请输入四位会员卡号:");
        Scanner input=new Scanner(System.in);//导包
        cusNO=input.nextInt();
        //获得 每位数字
        int gewei=cusNO%10;
        int shiwei=cusNO%10%10;
        int baiwei=cusNO/100%10;
        int qianwei=cusNO/1000;
        int sum=gewei+shiwei+baiwei+qianwei;
        System.out.println("会员卡号:"+cusNO+"各位之和:"+sum);
        boolean isluck=sum>20;//boolean的判断为true或false
        System.out.println("是幸运客户吗?"+isluck);
    }
}

  
//我行我素,判断商品判断商品折扣价格
    public static void main(String[] args) {
        int shirtPrice=245;
        int shoePrice=570;
        int padPrice=320;
        //用户输入折扣
        Scanner input=new Scanner(System.in);
        System.out.println("请输入折扣：");
        double discount=input.nextDouble();
        //计算商品的享受价格
        double shirtPriceDis=shirtPrice*discount;
        double shoePriceDis=shoePrice*discount;
        double padPriceDis=padPrice*discount;
        //判断商品价格是否低于100
        boolean shirtPricebool=shirtPriceDis<100;
        boolean shoePricebool=shoePriceDis<100;
        boolean padPricebool=padPriceDis<100;
        System.out.println("T血折扣低于100吗？"+shirtPricebool);
        System.out.println("网球鞋折扣低于100吗？"+shoePricebool);
        System.out.println("网球拍折扣低于100吗？"+padPricebool);
         
          
小明左右手分别拿出两张牌
public static void main(String[] args) {
    int num;
    int num1;
    System.out.println("输出互换前手中的纸牌 ：");
    
         Scanner input=new Scanner(System.in);
         System.out.println("左手中的纸牌:\n");
        num=input.nextInt();
        System.out.println("输出右手的纸牌：");
            num1=input.nextInt();
            System.out.println("**************************************");
            System.out.println("输出互换后手中的纸牌 ：");
            int temp;
            temp=num;
            num=num1;//20
            num1=temp;//10
            System.out.println("左手中的纸牌:"+num);
            System.out.println("输出右手的纸牌："+num1);
    }
}

  
 double sheshi=0;
            int num=0;//循环次始值
            double huashi;
            do{
                num++;
                sheshi+=20;
                huashi=sheshi*9/5+32;
                System.out.println("摄氏温度:"+sheshi+"度,华氏温度:"+huashi+"度");
            }while(num<=9);//循环次条件
            System.out.println("结束");
    
   
public static void main(String[] args) { 
         Scanner input=new Scanner(System.in);
        /*
         * 产生随机数
         * */
         int random=(int)(Math.random()*10);
         System.out.println("************购物系统抽奖************\n");
         System.out.println("请输入4位会员号：");
         int cusNo=input.nextInt();
         /*
          * 获得百分位
          * */
         int baiwei=cusNo/100%10;
         /*
          * 判断该会员是否是幸运会员
          * */
         if (baiwei==random)          
             System.out.println(cusNo+"是幸运客户，获得笔记本一个");
             
        }else {
            System.out.println(cusNo+"号客户"+"谢谢");
        }
    } 
public static void main(String[] args) {
        
         Scanner input=new Scanner(System.in);
         System.out.println("请输入第一个整数");
         int a=input.nextInt();
         System.out.println("请输入第二个整数");
         int b=input.nextInt();
         System.out.println("请输入第三个整数");
         int c=input.nextInt();
         /*第一道排序*/
         System.out.println("第一道排序");
         if (a<b&&a<c) {
            System.out.print(a);
            System.out.print(b);
            System.out.println(c);
        }
         /*第二道排序*/
         System.out.println("第二道排序");
         if (b<c) {
            System.out.print(a);
            System.out.print(b);
            System.out.println(c);
        }
         System.out.println("每个变量的值");
            System.out.println(a);
            System.out.println(b);
            System.out.println(c);
    } 
    public static void main(String[] args) {
        int price = 5000;  // 机票的原价
        int month;  // 出行的月份
        int type;   // 头等舱为1,经济舱为2
        Scanner input = new Scanner(System.in);
        System.out.println("请输入您出行的月份：1～12");
        month = input.nextInt();
        System.out.println("请问您选择头等舱还是经济舱？头等舱输入1，经济舱输入2");
        type = input.nextInt();
        
        switch(month/10){
            case 1:
            case 2:
            case 3:
                 if (type == 1) // 头等舱
                    {
                        System.out.println("您的机票价格为："+ price * 0.6);
                    }
                    else if (type == 2)  // 经济舱
                    {
                        System.out.println("您的机票价格为："+ price * 0.3);
                    }                
                break;
            case 0:
            case 4:
            case 5:
            case 6:
            case 7:
            case 8:
            case 9:
                 if (type == 1) // 头等舱
                    {
                        System.out.println("您的机票价格为："+price * 0.9);
                    }
                    else if (type == 2)  // 经济舱
                    {
                        System.out.println("您的机票价格为："+ price * 0.8);
                    }                
                break;
            default:
                System.out.println("请正确输入成绩！");
                break;
        }
        
         
public static void main(String[] args) {
    Scanner input=new Scanner(System.in);
    System.out.println("*******************计算器****************");
    int result=0;
    char opt='*';   //定义操作符
    System.out.println("请输入第一个操作数：");
    if (input.hasNextInt() == true) {
        int num1 = input.nextInt();
        System.out.println("请输入第二个操作数：");
        if (input.hasNextInt() == true) {
            int num2 = input.nextInt();
            switch (opt) {
            case '+':
                result=num1+num2;
                break;
            case '-':
                result=num1-num2;
                break;
            case '*':
                result=num1*num2;
                break;
            case '/':
                result=num1/num2;
                break;
            default:
                System.out.println("输入错误。");
                break;
            }
            System.out.println("计算结果："+num1+""+opt+num2+"="+result);
        }else {
            System.out.println("请输入正确的数字!");
        }
    } else {
        System.out.println("请输入正确的数字!");
    } 
public static void main(String[] args) {
    Scanner input=new Scanner(System.in);
    System.out.println("*******************系统*************");
    System.out.println("1.进入");
    System.out.println("2.退出");
    System.out.println("请输入数字");
    /*
     * 通过调用Scanner对象的hasNextInt()，来判断输入的数字是否合法
     * */
    if (input.hasNextInt()==true) {
        int num=input.nextInt();
        switch (num) {
        case 1:    
            System.out.println("don't go");
            break;
    case 2:        
        System.out.println("let go");
            break;
        default:
            System.out.println("错误");
            break;
        }
    }
     
public static void main(String[] args) {
        //方法一：
        /*100以内的偶数之和
         * */
    int num=0;
    int sum=0;
    while (num<=100) {
        if (num%2==0) {
            sum+=num;
        }
        num++;
    }
            System.out.println(sum);
            //方法二：
            while (num<=100) {            
                    sum+=num;                
                  num+=2;
            }
                    System.out.println(sum);
                
                    
     } 
public static void main(String[] args) {
        Scanner input=new Scanner(System.in);
        System.out.println("请选择编号：\n 1.T血，2.网球鞋，3.网球拍");
    
        
        double price=0.0;
        String name="";
        int goodsno=0;
        String answer="y";
        while ("y".equals(answer)) {
            System.out.println("请输入编号：");
            goodsno=input.nextInt();
            switch (goodsno) {
            case 1:
                name="djs";
                price=245.0;
                break;
            case 2:
                name="fd";
                price=570.0;
                break;
            case 3:
                name="res";
                price=320.0;
                break;
            default:
                break;
            }
            System.out.println(name+"\t"+"￥"+price+"\t");
            System.out.println("是否继续？（y/n）");
            answer=input.next();
        }
        System.out.println("程序结束");
    } 
public static void main(String[] args) {
        //01.列出商品清单
                System.out.println("1.T恤 2.网球鞋  3.网球拍");
                //02.肯定要用到循环
                String answer="";
                //定义折扣
                double discount=0.8;
                //保存总金额
                double money=0;
                Scanner input=new Scanner(System.in);
                
                do{
                    System.out.println("请输入商品编号");
                    
                    int proNo=input.nextInt();
                    System.out.println("请输入商品数量");
                    int proNum=input.nextInt();
                    String proName="";
                    double proPrice=0;
                    switch (proNo) {
                    case 1:
                        //列出第一个商品的信息
                        //名称
                         proName="T恤";
                        //价格
                         proPrice=25;
                        break;
                    case 2:
                         proName="网球鞋";
                         proPrice=260;
                        break;
                    case 3:
                         proName="网球拍";
                         proPrice=200;
                        break;
                    default:
                        break;
                    }
                    //03.输出当前所购买商品的详情
                    double sum=proPrice*proNum;
                    money=money+sum;
                    System.out.println(proName+"\t￥"+proPrice+"\t数量"+proNum+"\t小计"+sum);
                    System.out.println("是否继续?(y/n)");
                    answer=input.next();
                }while(answer.equals("y"));
                //出了循环，意味着用户要结账，离开商店
                System.out.println("折扣："+discount);
                //应付金额
                double yingfuMoney=money*discount;
                System.out.println("应付金额："+yingfuMoney);
                System.out.println("请输入您的支付金额：");
                int userMoney=input.nextInt();
                //找零
                double lastMoney=userMoney-yingfuMoney;
                //最好判定一下
                if (userMoney>=yingfuMoney) {
                    System.out.println("找零"+lastMoney);
                } 

            //用户录入一堆数字，拎出最大和最小值
        Scanner input=new Scanner(System.in);
        System.out.println("爷爷，请您输入一个数字呗");
        int num=input.nextInt();
        //最大值
        int max=num;
        //最小值
        int min=num;
        while(num!=0){
            if(num>max){
                max=num;
            }
            if(num<min){
                min=num;
            }
            System.out.println("爷爷，请您输入一个数字呗");
            num=input.nextInt();
        }
        System.out.println("最大值是"+max+"\t最小值是"+min);
                
 


public static void main(String[] args) {
            Scanner input=new Scanner(System.in);
    int cource=0;
        int number=0;//班级总人数
          int sum=0;//大于80分的人数
          System.out.println("总人数：");
         number =input.nextInt();
         for (int i =0; i <number; i++) {
            System.out.println("输入第"+(i+1)+"位成绩");
            cource=input.nextInt();
            if (cource<80) {
                continue;
            }
            sum++;
        }
         System.out.println("80分以上的人数"+sum);
         double rate=(double)sum/number*100;
         System.out.println("比例："+rate+"%");
    }        

public static void main(String[] args) {
            Scanner input=new Scanner(System.in);
        int sum=0;
        int coure=0;
        int avg=0;
        boolean isnegi=false;
        //Scanner input=new Scanner(System.in);
        for (int i =0; i <5; i++) {    
            System.out.println("请输入5门课程的"+(i+1)+"门课的成绩：");
            coure=input.nextInt();
            if (coure<0) {
                isnegi=true;
                break;
            }
            sum+=coure;
        }
        if (isnegi) {
            System.out.println("成绩输入错误");
        }else {
            avg=sum/5;
            System.out.println("总成绩："+sum);
            System.out.println("平均成绩："+avg);
        }

     
public static void main(String[] args) {
            Scanner input=new Scanner(System.in);
int pwd=123456;//密码
        String name="jim";//户名s        
        for (int i = 0; i <3; i++) {
            System.out.println("请输入用户名：");
            String Rname=input.next();
            System.out.println("请输入密码：");
            int Rpwd=input.nextInt();
            if (Rname.equals(name)&&Rpwd==pwd) {
                System.out.println("欢迎登陆系统");
                
            }else {
                System.out.println("输入错误!您还有"+(3-(i+1))+"次机会");
                System.out.println("对不起！"+((i+1))+"次错误！");
                continue;
                
            }        
        } 
        int rabbit;//兔子
         int chicken;//小鸡
         for(rabbit=1;rabbit<14;rabbit++){
          chicken=35-rabbit;
          if((rabbit*4+chicken*2)==94)
           System.out.println("兔子:"+rabbit+"\t小鸡:"+chicken);        
         }

  
for (int i = 1; i <=100; i++) {
            
            if (i%3==0) {
                System.out.println("Flip");
            }
                else {
                    System.out.println(i);
                }
            if (i%5==0) {
                System.out.println("Flop");
            }
                else {
                    System.out.println(i);
                }
         if (i%3==0&&i%5==0) {
                System.out.println("FlipFlop");
            }else {
                System.out.println(i);
            }
        }

  
int men;
        int women;
        for( men=0;men<=10;men++){
            for( women=0;women<=30;women++){
                if(30-men-women >= 0){
                    int count = 3*men + 2*women + 1*(30-men-women) ;
                    if(count == 50){
                        System.out.println("男人:" + men+",女人:"+women+",小孩:" +(30-men-women)) ;
                    }
                }
            }
        }

  
public static void main(String[] args) {
        Scanner input=new Scanner(System.in);    
        /*
         *选择游戏
         * 
         * */
        System.out.println("欢迎进入青鸟迷你戏平台");
        System.out.println("");
        System.out.println("请选择你喜爱的游戏");
        System.out.println("----------------------------");
        System.out.println("1.斗地主");
        System.out.println("2.斗牛");
        System.out.println("3.泡泡龙");
        System.out.println("4.连连看");
        System.out.println("-----------------------------");
        System.out.println("请选择,输入数字:");
        int num = input.nextInt();
        switch (num) {
        case 1:
            System.out.println("您已进入斗地主房间!");
            break;
        case 2:
            System.out.println("您已进入斗牛房间!");
            break;
        case 3:
            System.out.println("您已进入泡泡龙房间!");
            break;
        case 4:
            System.out.println("您已进入连连看房间!");
            break;
        }
                /*
                 * 玩游戏升级
                 * 
                 * */
        int score = 0;
        int Num = 1;
        String answer;
        do {
            System.out.println("您正在玩" + Num + "局,输入您的成绩为:");
            score = input.nextInt();
            if (score > 80) {
            }
            Num++;
            if (Num > 5) {
                System.out.println("游戏结束!!");
                System.out.println("恭喜你,通过一级");

            } else {
                System.out.println("继续玩下一局吗?(yes/no)");
                answer = input.next();
                if (answer.equals("no")) {
                    System.out.println("您已中途退出游戏");
                    System.out.println("对不起,您未能晋级,继续加油呀!");
                    break;
                } else {
                    System.out.println("进入下一局");
                }
            }
        } while (Num <= 5);
        
        /*玩游戏并支付游戏币
         * 
         * */
        int money;
        double discount1 = 0.5;
        double discount2 = 0.8;
        int m1 = 10;
        int m2 = 20;
        System.out.println("请您选择玩的游戏类型:");
        System.out.println("1.牌类");
        System.out.println("2.休闲竞技类");
        int num1 = input.nextInt();
        System.out.println("请您输入游戏时长:");
        int time = input.nextInt();
        switch (num1) {
        case 1:
            if (time > 10) {
                System.out.println("您玩的是牌类游戏,时长是:" + time + "小时,可以享受5折优惠");
                money = (int) (time * m1 * discount1);
                System.out.println("您需支付" + money + "个游戏币");

            } else {
                System.out.println("您玩的是牌类类游戏,时长是:" + time + "小时,可以享受8折优惠");
                money = (int) (time * m1 * discount2);
                System.out.println("您需支付" + money + "个游戏币");
            }
            break;
        case 2:
            if (time > 10) {
                System.out.println("您玩的是休闲类游戏,时长是:" + time + "小时,可以享受5折优惠");
                money = (int) (time * m2 * discount1);
                System.out.println("您需支付" + money + "个游戏币");

            } else {
                System.out.println("您玩的是休闲类游戏,时长是:" + time + "小时,可以享受8折优惠");
                money = (int) (time * m2 * discount2);
                System.out.println("您需支付" + money + "个游戏币");
            }
            break;
        }
        /*统计游戏点击率
         * 
         * */
        int j = 0;
        int num2 =0;
        for (int i = 1; i <= 4; i++) {
            System.out.println("请输入第" + i + "个游戏的点击率:");
            num2 = input.nextInt();
            if (num2 <= 100) {
                continue;
            }
            j++;
        }
        System.out.println("点击率大于100的游戏数是:" + j);
        double rate = (double)j/ 4 * 100;
        System.out.println("点击率大于100的游戏所占的比例是:" + rate + "%");
        /*添加用户信息
         * 
         * */
        int a=0,age=0,b=0;
        System.out.println("请输入要登录用户的数量:");
        int num3=input.nextInt();
        for (int i=0;i<num3;i++){
            System.out.println("请输入用户编号<4位整数>:");
             a=input.nextInt();
             System.out.println("请输入用户年龄:");
             age=input.nextInt();
             System.out.println("请输入用户积分:");
             b=input.nextInt();
             if(age<10){
                 System.out.println("很抱歉,你年龄不适合玩游戏\n录入失败");
             }else{
             System.out.println("您输入的会员信息是:");
                System.out.println("用户编号"+a+"\t用户年龄"+age+"\t用户积分"+b);
        }
        }

    }
     
public static void main(String[] args) {            
        
        Scanner input=new Scanner(System.in);
System.out.println("请输入整数：");
        int in=input.nextInt();
        int result=1;
        System.out.print(in+"!=");
        for (int i = 1; i<=in; i++) {
                        System.out.print(i);
            if (i<in) {
                System.out.print("*");
                
            }
            result=result*i;
            
        }
        System.out.print("="+result);
        }
 


 
public static void main(String[] args) {                
        Scanner input=new Scanner(System.in);
        int num = 0; //个数
        int sum = 0; //和
        for(int i = 0;i <= 100;i ++) { 
        if(i % 7!= 0) { 
        num ++; 
        sum = sum+i; 
        System.out.print(i + "\t"); 
        if(num % 4 == 0) 
        System.out.println(); 
        }          
        } 
        System.out.println(); 
        System.out.println("总和为:"+sum);
        
      
        Scanner input=new Scanner(System.in);
        
        int scores []=new int[5];
        int sum=0;
        
        System.out.println("请输入五位同学的成绩：");
        for (int i = 0; i < scores.length; i++) {
            scores[i]=input.nextInt();
            sum+=scores[i];//成绩累加        
        }
        System.out.print("平均分："+sum/scores.length);
        
 

int scores []=new int[]{90,80,100,95,90};
        System.out.println("请修改第三位同学的成绩为98:");
        scores[2]=98;//数组下标
        System.out.println("修改后，五位同学的成绩：");
        for (int i = 0; i < scores.length; i++) {
            System.out.print(scores[i]+" ");
        }
  

public static void main(String[] args) {                
        Scanner input=new Scanner(System.in);
        double sum=0;
        double scores[]=new double[5];
        for (int i = 0; i < scores.length; i++) {
            System.out.print("请输入第"+(i+1)+"笔金额的记录:");
            scores[i]=input.nextDouble();
             sum+=scores[i];
        }
        System.out.println("序号\t\t"+"金额(元)");
        for (int i = 0; i < scores.length; i++) {
            System.out.print((i+1)+"\t\t");
        System.out.println(scores[i]);
        }
            System.out.println("总金额：\t\t"+sum);

  
    public static void main(String[] args) {        
    Scanner input=new Scanner(System.in);
    int scores []=new int[5];
    System.out.println("请输入5位同学的成绩：");
    //录入成绩
    for (int i = 0; i < scores.length; i++) {
        scores[i]=input.nextInt();
    }
    Arrays.sort(scores);//排序
    System.out.println("学员成绩按升序排序：");
    for (int i = 0; i < scores.length; i++) {
        System.out.println(scores [i]+" ");
    }
 

public static void main(String[] args) {        
    Scanner input=new Scanner(System.in);
    int scores []=new int[5];
    int max=0;
    System.out.println("请输入5位同学的成绩：");
    //录入成绩
    for (int i = 0; i < scores.length; i++) {
        scores[i]=input.nextInt();
    }
    
    for (int i = 0; i < scores.length; i++) {
        if (scores[i]>max) {
            max=scores[i];
        }
    }
        System.out.println("最高分："+max);
    }
  
public static void main(String[] args) {        
    Scanner input=new Scanner(System.in);
           int [] list=new int [6];
           list[0]=99;
           list[1]=95;
           list[2]=92;
           list[3]=89;
           list[4]=69;
           list[5]=49;
           int index=list.length;//保存新增成绩的位置
           System.out.println("请输入新增成绩：");
           int num=input.nextInt();//输入要插入的数据
           //找到新元素插入的位置
           for (int i = 0; i < list.length; i++) {
            
               if (num>list[i]) {
                index=i;
                break;
            }
        }
           //元素后移
           for (int i =list.length-1 ; i >index ; i--) {
        list[i]=list[i-1];//index下标开始的元素后移一个位置
        }
           list[index]=num;
    System.out.println("插入成绩的下标："+index);
    
    System.out.println("插入后成绩信息是：");
    for (int i = 0; i < list.length; i++) {
        System.out.println(list[i]+"\t");
    }
    }
  
public static void main(String[] args) {        
    Scanner input=new Scanner(System.in);
    String[]num=new String[]{"a","c","u","b","e","p","f","z"};
    System.out.print("原字符序列:");
    for (int i = 0; i < num.length; i++) {
        System.out.print(num[i]+" ");
    }
    Arrays.sort(num);
    System.out.println();//换行
    System.out.print("升序排序后:");
    for (int i = 0; i < num.length; i++) {
        System.out.print(num[i]+" ");
    }
    System.out.println();//换行
    System.out.print("逆序输出为:");
    //逆序，则从最后的哪一个元素排在第一位
    for (int i = num.length-1; i >=0 ; i--) {
        System.out.print(num[i]+" ");
    } 
 
Scanner input=new Scanner(System.in);
    String[]num=new String[]{"a","c","u","b","e","p","f","z"};
    System.out.print("原字符序列:");
    for (int i = 0; i < num.length; i++) {
        System.out.print(num[i]+" ");
    }
    Arrays.sort(num);
    System.out.println();//换行
    System.out.print("升序排序后:");
    for (int i = 0; i < num.length; i++) {
        System.out.print(num[i]+" ");
    }
    System.out.println();//换行
    System.out.print("逆序输出为:");
    //逆序，则从最后的哪一个元素排在第一位
    for (int i = num.length-1; i >=0 ; i--) {
        System.out.print(num[i]+" ");
    }
  int index=num.length;//待插入的字符的位置
  System.out.println();
  System.out.print("待插入的字符:"); 
  String way=input.next();//输入要插入的位置
  //找到要插入字符的位置
  for (int i = 0; i < num.length; i++) {
    if (way.equalsIgnoreCase(num[i])) {
        index=i;
        break;
    }
}
  //元素后移
  for (int i =num.length-1; i >index; i--) {
    num[i]=num[i-1];
}
  num[index].equals(way);//插入数据
  System.out.println("插入字符的下标:"+index);
  System.out.println("插入后字符的信息是:");
  for (int i = 0; i < num.length; i++) {
    System.out.println(num[i]+"\t");
}
 
Scanner input=new Scanner(System.in);
     System.out.println("请输入4家店的价格");
       int[]num=new int[4];
       for (int i = 0; i < num.length; i++) {
               System.out.print("第"+(i+1)+"店的价格:");
               num[i]=input.nextInt();           
           }
       int min=num[0];
        int index=0;
           for (int j = 0; j < num.length; j++) {
            if (num[j]<min) {
                min=num[j];
                index=j;
            }
            
           }
           System.out.print("最低价格:"+min);
           System.out.println("且它在数组中的原始位置(下标)是:" + index);
        }
    }
        
        
    }
  
    Scanner input=new Scanner(System.in);
       String []num= new String[5];
       System.out.println("请输入5句话");
       for (int i = 0; i < num.length; i++) {
        System.out.print("第"+(i+1)+"句话:");
        num[i]=input.next();
      }
       System.out.println();
       System.out.println("逆序输出的5句话:");
       for (int i =num.length-1; i>=0 ; i--) {
        System.out.print(num[i]+" ");
    }      
int[] points = { 18, 25, 7, 36, 13, 2, 89, 63 };
        System.out.println("8位顾客的积分:");
        for (int i = 0; i < points.length; i++) {
            System.out.print(points[i] + "\t");
        }
        System.out.println();
        int min = 0;
        int index = 0;
        min = points[0];
        for (int i = 1; i < points.length; i++) {
            if (points[i] < min) {
                min = points[i];
                index = i;
            }
        }
        System.out.println("其中最低积分:" + min);
        System.out.println("且它在数组中的原始位置(下标)是:" + index);
    }
  
Scanner input=new Scanner(System.in);
        int nums[] = new int[10];
        int a = 0;
        int b = 0;
        int c = 0;
        int d = 0;
        System.out.println("请输入10个数:");
        for (int i = 0; i < nums.length; i++) {
            nums[i] = input.nextInt();
        
            switch (nums[i]) {
            case 1:
                a++;
                break;
            case 2:
                b++;
                break;
            case 3:
                c++;
                break;
            default:
                d++;
                break;
            }
            
        }
        System.out.println("数字1的个数:"+a);
        System.out.println("数字2的个数:"+b);
        System.out.println("数字3的个数:"+c);
        System.out.println("非法数字的个数:"+d);

  
Scanner input=new Scanner(System.in);
            
    int []array=new int[]{1,3,-1,5,-2};
    System.out.println("原数组的为:");
    for (int i = 0; i < array.length; i++) {
        System.out.print(array[i]+ " ");
    }
    System.out.println();
      int newarray[]=new int[5];
      for (int i = array.length - 1; i >= 0; i--) {
            if (array[i] < 0) {
                continue;
            }
            if (array[i] > 0) {
                newarray[array.length - i - 1] = array[i];
            }
        }
        System.out.println("");
        System.out.println("逆序并处理后的数组为:");
        for (int i = 0; i < newarray.length; i++) {
            System.out.print(newarray[i]+" ");
        }
         }  
public static void main(String[] args) {        
        Scanner input=new Scanner(System.in);    
    int [] score=new int[4];
    int classNum=3;
    double Sum=0.0;//成绩总和
    double []average=new double[classNum];//平均成绩数组
    //循环输入学员成绩
    for (int i = 0; i <classNum; i++) {
        Sum=0.0;//成绩总和归零
        System.out.println("请输入第"+(i+1)+"个班的成绩");
        for (int j = 0; j < score.length; j++) {
            System.out.print("第"+(j+1)+"个学员的成绩:");
            score[j]=input.nextInt();
            Sum=Sum+score[j];
        }
        average[i]=Sum/score.length;//计算平均分
        System.out.println("第"+(i+1)+"个班级参赛学员的总成绩:"+Sum);
        System.out.print("第"+(i+1)+"个班级参赛学员的平均分是:"+average[i]+" \n");
    }
        
        }
      
public static void main(String[] args) {        
        Scanner input=new Scanner(System.in);    
    
        
        int [] score=new int[4];
        int classNum=3;
        double Sum=0.0;//成绩总和
        int count=0;//记录80分以上的人数
        double []average=new double[classNum];//平均成绩数组
        //循环输入学员成绩
        for (int i = 0; i <classNum; i++) {
            Sum=0.0;//成绩总和归零
            System.out.println("请输入第"+(i+1)+"个班的成绩");
            for (int j = 0; j < score.length; j++) {
                System.out.print("第"+(j+1)+"个学员的成绩:");
                score[j]=input.nextInt();
                Sum=Sum+score[j];
                if (score[j]<85) {//成绩小于85，则跳出本次循环
                    continue;
                }
                count++;
            }
            average[i]=Sum/score.length;//计算平均分
            System.out.println("第"+(i+1)+"个班级参赛学员的总成绩:"+Sum);
            System.out.print("第"+(i+1)+"个班级参赛学员的平均分是:"+average[i]+" \n");
            System.out.println("成绩85分以上的人数:"+count+"人");
        }
              
    Scanner input=new Scanner(System.in);    
    System.out.println("请输入直角三角形的行数:");
    int Rownum=0;
    Rownum=input.nextInt();
    for (int i = 1; i <=Rownum; i++) {//行数
        for (int j = 1; j <=i*2-1; j++) {//星数
            System.out.print("☆");
        }
        System.out.println();
    }
        }  
        Scanner input=new Scanner(System.in);    
    System.out.println("请输入倒直角三角形的行数:");
    int Rownum=0;
    Rownum=input.nextInt();
    for (int i = 1; i <=Rownum; i++) {//行数
        for (int j = 1; j <=10-i; j++) {
            System.out.print("*");
        }
        System.out.println("");
    }

        }  
    Scanner input=new Scanner(System.in);    
    System.out.println("请输入等腰三角形的行数:");
    int Rownum=0;
    Rownum=input.nextInt();
    for (int i = 1; i <=Rownum; i++) {//行数
        for (int j = 0; j <Rownum-i; j++) {//空格数
            System.out.print(" ");        
        }
        for (int k = 1; k <=2*i-1; k++) {//星星数
            System.out.print("*");
        }
        System.out.println("");
        
        
    }  
public static void main(String[] args) {        
        Scanner input=new Scanner(System.in);    
    int Rownum=9;
    for (int i = 1; i <=Rownum; i++) {//行数
        for (int j = 1; j <=i; j++) {//空格数
            System.out.print(j+"*"+i+"="+j*i+" ");        
        }
        System.out.println("");
        
        
    }  
public static void main(String[] args) {        
        Scanner input=new Scanner(System.in);    
    int count=0;//计数器
    String choice="";//顾客选择是否离开
            for (int i = 0; i <5; i++) {
                System.out.println("欢迎光临第"+(i+1)+"家专卖店");
            for (int j = 0; j <3; j++) {
                System.out.println("要离开吗?(y/n)");
            choice=input.nextLine();
            //如果离开，则跳出，进入下一家店
            if ("y".equals(choice)) {
            break;
            }
            System.out.println("买了一件衣服");
            count++;
            }
            System.out.println("离店结账");
            }
            System.out.println("总共买了"+count+"件衣服");
            choice=input.nextLine();
        
  
    int way = 1;    //买法
        int k = 0;    //雏鸡数
        for(int i=1;i<=20;i++){        //公鸡数
            for(int j=1;j<=33;j++){    //母鸡数
                k = 100-i-j;        //一共100只鸡
                if(k%3 == 0 && (5*i+3*j+k/3 == 100)){//雏鸡数是3的倍数，总计100文钱
                    System.out.print("买法 " + way++ + ": ");
                    System.out.println("公鸡: " +i+ "    母鸡：" +j+ "     雏鸡：" +k);

                }
            }
        }  
    Scanner input=new Scanner(System.in);    
    
        int[] score = new int[4];//从零开始，0,1,2,3数    ，//成绩数组
                int classnum = 3;                        //班级数目
                double sum = 0.0;                        //成绩总和
                double average = 0.0;                    //平均成绩
                int count = 0;                            //记录85分以上学员人数
                
                //循环输入学员成绩
            
                for(int i = 0; i < classnum; i++){
                    System.out.println("请输入第" + (i+1) + "个班级的成绩");
                    for(int j = 0; j < score.length; j++){
                        System.out.print("请输入第" + (j+1) + "个学员的成绩：");
                        score[j] = input.nextInt();
                        if(score[j] < 85){    //成绩小于85，则跳出本轮循环
                            continue;
                        }
                        sum = sum + score[j];            //成绩85分以上才进行累加
                        count++;
                    }        
                }
                average = sum / count;                    //所有成绩85分以上的学员的平均分
                System.out.println("所有成绩85分以上的学员的平均分为：" + average);
  
Scanner input=new Scanner(System.in);    
        String pass = "";                //保存用户输入密码
        int amount = 0;                    //取款金额
        String password = "111111";        //用户密码
        int count = 0;                    //记录密码输入次数
        boolean isPass = false;            //密码是否通过验证
        while(count < 3 && !isPass){
            System.out.print("请输入密码：");
            pass = input.next();
            if(!password.equals(pass)){
                count++;
                continue;
            }
            isPass = true;                //密码通过验证
            System.out.print("请输入金额：");
            amount = input.nextInt();
            while(amount>0){
                if(amount<=1000 && amount%100==0){
                    System.out.println("您取了" +amount+ "元");
                    System.out.println("交易完成，请取卡！");
                    break;                //完成交易，退出
                }else{
                    System.out.print("您输入金额的金额不合法，请重新输入：");
                    amount = input.nextInt();
                    continue;            //继续让用户输入金额
                }
            }
        }
        if(!isPass){                    //用户输入了3次错误密码
            System.out.print("密码错误，请取卡！");
        }  
Scanner input=new Scanner(System.in);    
        int rows = 0;    //菱形的行数
        System.out.print("请输入菱形行数：");
        rows = input.nextInt();

        while(rows%2 == 0){
            System.out.print("请输入奇数：");
            rows = input.nextInt();
        }

        int n = (rows+1)/2;
        //打印菱形的上半部分
        for(int i = 1; i <= n; i++){//外层循环变量i控制行数
            for(int j = 1; j <= n-i; j++){//内层循环变量j控制该行空格数
                System.out.print(" ");
            }
            for(int k = 1; k <= 2*i-1; k++){//内层循环变量k控制该行*号数
                System.out.print("*");
            }
            System.out.print("\n");
        }
        //打印菱形的下半部分
        for(int i = n-1; i >= 1; i--){
            for(int j = 1; j <= n-i; j++){
                System.out.print(" ");
            }
            for(int k = 1; k <= 2*i-1; k++){
                System.out.print("*");
            }
            System.out.print("\n");
        }  
    Scanner input = new Scanner(System.in);
        String answer = "";
        boolean a = false;
        boolean b = false;
        do {
            System.out.println("*********欢迎**********");
            System.out.println("1.注册");
            System.out.println("2.登录");
            System.out.println("3.抽奖");
            System.out.println("请输入:");
            int num = input.nextInt();
            switch (num) {
            case 1:
                System.out.println("您选择的是注册");
                System.out.println("请填写个人注册信息");
                System.out.println("用户名:");
                String name = input.next();
                System.out.println("密码:");
                int nums = input.nextInt();
                int random = (int) (Math.random() * 9000) + 1000;
                System.out.println("用户名\t密码\t会员号");
                System.out.println(name + "\t" + nums + "\t" + random);
                a = true;
                System.out.println("是否继续(y/n)");
                answer = input.next();
                break;
            case 2:
                if (a == true) {
                    System.out.println("您选择的是登录");
                    System.out.println("请输入您的用户名:");
                    name = input.next();
                    System.out.println("请输入密码:");
                    nums = input.nextInt();
                    System.out.println("欢迎您" + name);
                    b = true;
                } else {
                    System.out.println("请您先注册,亲");
                }
                System.out.println("是否继续(y/n)");
                answer = input.next();
                break;
            case 3:
                int random1 = (int) (Math.random() * 9000) + 1000;
                if (b == true) {
                    System.out.println("您选择的是抽奖");
                    System.out.println("请输入您的卡号:");
                    int kahao = input.nextInt();
                    System.out.println("本日的幸运数字为");
                    for (int i = 0; i < 5; i++) {
                        random1 = (int) (Math.random() * 9000) + 1000;
                        System.out.print(random1+"\t");
                    }
                    if (kahao == random1) {
                        System.out.println("恭喜您,您中奖了");
                        System.out.println("是否继续(y/n)");
                        answer = input.next();

                    } else {
                        System.out.println("对不起!您不是本日的幸运会员.");
                        System.out.println("是否继续(y/n)");
                        answer = input.next();

                    }

                } else {
                    System.out.println("请先登录,亲");
                    System.out.println("是否继续(y/n)");
                    answer = input.next();

                }
                break;
            default:
                System.out.println("输入错误!");
                System.out.println("是否继续(y/n)");
                answer = input.next();
                break;
            }

        } while (answer.equals("y"));
        System.out.println("退出");
  
public class School {
    /*
     * School类的属性
     * */
String schName;//名称
int classNumber;//教室数目
int labNumber;//机房数目
/*
 * School类的Show方法
 * */
public void Show(){
    System.out.println(schName+"培训中心\n"+"配备:"+
classNumber+"教"+labNumber+"机");

    public static void main(String[] args) {        
        School sch=new School();
        System.out.println("*******初始化成员变量前*******");
        sch.Show();
        sch.schName="北京";
        sch.classNumber=20;
        sch.labNumber=30;
        System.out.println("\n**********初始化变量后**************");
        sch.Show();
         

public class Student {
/*Student的属性
 * */
    String name;
    int age;
    String classNo;//班级
    String hobby;//爱好
    /*Student的方法
     * */
    public void showStudent(){
        System.out.println("姓名:"+name+"\n年龄:"+age+"\n就读于:"+classNo+"\n爱好:"+hobby);
        
    }
}
public static void main(String[] args) {    
Student stu=new Student();
        stu.name="小小";
        stu.age=15;
        stu.classNo="S1";
        stu.hobby="打篮球";
        stu.showStudent();
  
public class Visitor {
String name;
int age;
public void Show(){
    Scanner input=new Scanner(System.in);
    while (!"n".equals(name)) {
        if (age>=18&&age<=60) {
            System.out.println(name+"的年龄为:"+age+",门票价格为:20元\n");
        }else {
            System.out.println(name+"的年龄为:"+age+",门票免费\n");
        }
        System.out.println("请输入姓名:");
        name=input.next();
        if (!"n".equals(name)) {
            System.out.print("请输入年龄:");
        age=input.nextInt();//给age属性赋值
        }
    }
    System.out.println("退出程序");
   }

    public static void main(String[] args) {
        //************Visitor**********
        Scanner input=new Scanner(System.in);
        Visitor v=new Visitor();
        System.out.println("请输入姓名:");
        v.name=input.next();
        System.out.println("请输入年龄:");
        v.age=input.nextInt();
        v.Show();
          
public class Administrator {
public String name;
public String password;

}
public class OneDay {
    public static void main(String[] args) {
        //************Visitor**********
        Scanner input=new Scanner(System.in);
    Administrator as=new     Administrator();
    as.name="admin";
    as.password="111111";
    //输入旧密码
     String chioce="";
do {
        System.out.println("请输入用户名:");
        String nameinput=input.next(); 
        System.out.println("请输入密码");
        String pass=input.next();
        //判断用户输入的用户名是否正确
        if (as.name.equals(nameinput)&&as.password.equals(pass)) {
            System.out.println("\n请输入新密码:");
        as.password=input.next();
        System.out.println("修改密码成功！！您的新密码:"+pass);
        
        }else {
            System.out.println("用户名和密码不匹配，您没有权利更改信息");
            System.out.println("还想继续吗?请输入(y/n)");
            chioce=input.next();
        }
    }while("y".equals(chioce));
    
        
        }
     
 
    public class Calcutor {
    public int num1;
    public int num2;
    public String yunsuan;
    
}
Scanner input =new Scanner(System.in); 
        Calcutor  calculator=new  Calcutor();
            System.out.println("请输入操作数");
             calculator.num1=input.nextInt();
             System.out.println("请输入运算符");
             calculator.yunsuan=input.next();
             char a=calculator.yunsuan.charAt(0);
             System.out.println("请输入操作数");
             calculator.num2=input.nextInt();
             switch(a){
             case '+':
                 System.out.println(calculator.num1+"+"+calculator.num2+"="+(calculator.num1+calculator.num2));
                 break;
 
 
public class Currentlor {
    public String time;
    public void show(){

    }
    public String time2;
    public void show(){
        
    } 
    public static void main(String[] args) {
        Scanner input =new Scanner(System.in); 
        Currentlor currentTime=new Currentlor();
        currentTime.time="2015年5月12日10点11分00秒";
        System.out.println(currentTime.time);
        currentTime.show();
        System.out.println("改后为");
        Domo domo=new Domo();
        domo.time2="2015年5月12日10点11分30秒";
        System.out.println(domo.time2);
        domo.show();

  
public class Season {
    String spring(){
        return "\n该季节为春季";
    }
    String summer (){
        return "\n该季节为夏季";
    }
    String autumn(){
        return "\n该季节为秋季";
    }
    String winter(){
        return "\n该季节冬季";
    }
}     

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Season sn=new Season();
        //获取输入
        /* 接收成绩 */
        Scanner input = new Scanner(System.in);
        System.out.print("请输入月份：");
        int mon = input.nextInt();
        switch(mon){
            case 1:
            case 2:
            case 3:
                System.out .println(sn.spring());
                break;
            case 4:
            case 5:
            case 6:
                System.out .println(sn.summer());
                break;
            case 7:
            case 8:
            case 9:            
                System.out .println(sn.autumn());
                break;
            case 10:
            case 11:
            case 12:
                System.out .println(sn.winter());
                break;
            default:
                    System.out .println("输入有误，请输入1~12月份数。");
                break;
            
        }     
  
public class GuessMachine {
    String name ;
       double price;
        
       /**
        * 初始化商品信息
        */
        public void initial(){
            int random = (int)(Math.random()*10);  //产生随机数
            switch(random){
              case 0:
              case 1:
              case 2:
              case 3: 
                  name = "公主电动车";
                  price = 2000;
                  break;
              case 4:
              case 5:
              case 6: 
                  name = "34寸纯平彩电";
                  price = 3000;
                  break;
              case 7:
              case 8:
              case 9:
                  name = "新飞冰箱";
                  price = 3400;
                  break;
              default: 
                  break;
            }  
        }   
        
        /**
         * 猜测
         */
        public void guess(){
            System.out.print("\n请猜测\""+ name + "\"的价格： " );
            Scanner input = new Scanner(System.in);
            double guessPrice = input.nextDouble();   //从键盘获取用户猜的价格;
            boolean isCorrect = false;
            for(int i = 0; i<3; i++){   //允许最多猜4次            
                if(guessPrice == price){   //判断是否猜对，并给出提示信息
                    System.out.println("猜对了！");
                    isCorrect = true;
                    break;
                }else if(guessPrice > price){
                    System.out.println("再小点！");
                }else{
                    System.out.println("再大点！");
                }
                System.out.print("\n再猜一次吧： ");
                guessPrice = input.nextDouble(); 
            }
            if(!isCorrect){
                System.out.println("\n4次内没有猜对，下次努力吧！");
            }}
public static void main(String[] args) {
        GuessMachine gm = new GuessMachine();
        gm.initial();
        gm.guess();
    }
  
public class Computer {
    public String nickName;
    public int fenshu;
    public int chuquan(){
        int num=(int)(Math.random()*3)+1;
        switch (num) {
        case 1:
            System.out.println("["+nickName+"]"+"您出的是剪刀");
            break;
        case 2:
            System.out.println("["+nickName+"]"+"您出的是石头");
            break;
        case 3:
            System.out.println("["+nickName+"]"+"您出的是布");
            break;
        default:
            break;
        }
        return num;
}

public class Judge {
    Computer computer = new Computer();
    Person person = new Person();
    int count = 0;
    String answer = "";

    public void result() {
        System.out.println("游戏结束了,比赛结果如下");
        System.out.println(person.nickName + "\tVS" + computer.nickName);
        System.out.println("我们一共玩了" + count + "局");
        System.out.println("其中我赢了" + person.fenshu + "局");
        if (person.fenshu > computer.fenshu) {
            System.out.println("我战胜了你");
        } else if (person.fenshu == computer.fenshu) {
            System.out.println("我们打了个平手");

        } else {
            System.out.println("我输了,其实我是让你的");
        }
    }

    public void getOnceResult() {
        Scanner input = new Scanner(System.in);
        System.out.println("您确定对战吗?(y/n)");
        answer = input.next();
        do {
            count++;
            int person1 = person.chuquan();
            int computer1 = computer.chuquan();
            if (person1 == 1 && computer1 == 2 || person1 == 2
                    && computer1 == 3 || person1 == 3 && computer1 == 1) {
                System.out.println("不好意思,我赢了");
                person.fenshu++;
            } else if (person1 == computer1) {
                System.out.println("我们平局");
            } else {
                System.out.println("我输了,你厉害");
                computer.fenshu++;

            }
            System.out.println("继续吗?(y/n)");
            answer = input.next();
        } while (answer.equals("y"));
    }

    public void menuList() {
        System.out.println("------------------欢迎进入天尽头猜拳系统--------------");
        System.out.println("\n\t\t******************");
        System.out.println("\n\t\t*****游戏开始了 ******");
        System.out.println("\n\t\t*******************");
        System.out.println("出拳规则：1.剪刀  2.石头   3.布");
        System.out.println("请选择对方角色：1.上帝    2.耶稣     3.佛祖");
        Scanner input = new Scanner(System.in);
        int num = input.nextInt();
        System.out.println("请输入您的大名:");
        person.nickName = input.next();
        switch (num) {
        case 1:
            computer.nickName = "上帝";

            System.out.println(person.nickName + ",您选择与上帝对战");

            break;
        case 2:
            computer.nickName = "耶稣";
            System.out.println(person.nickName + ",您选择与耶稣对战");

            break;
        case 3:
            computer.nickName = "佛祖";
            System.out.println(person.nickName + ",您选择与佛祖对战");
            break;
        default:
            break;
        }
    }

    public void Welcome() {
        menuList();
        getOnceResult();
        // 出了循环,打印结果
        if (answer.equals("n")) {
            result();

        }
public String nickName;
    public int fenshu;
    public int chuquan(){
        Scanner input=new Scanner(System.in);
        System.out.println("请出拳1.剪刀 2.石头 3.布 ");
        int num=input.nextInt();
        
        switch (num) {
        case 1:
            System.out.println(nickName+"您出的是剪刀");
            break;
        case 2:
            System.out.println(nickName+"您出的是石头");
            break;
        case 3:
            System.out.println(nickName+"您出的是布");
            break;
        default:
            break;
        }
        return num;
}

public static void main(String[] args) {
        Judge judge=new Judge();
        judge.Welcome();
    }

  
public class Loan {

    /**
     * 计算月供
     * @return money
     */
    public double loan(double loan,int yearchoice){
        double money=0;
    
        if(yearchoice==1){
            money=(loan+loan*0.0603)/36;
        }else if(yearchoice==2){
            money=(loan+loan*0.0612)/60;
        }else{
            money=(loan+loan*0.0639)/240;
        }        
        return money;
    }

/**
     * @param args
     */
    public static void main(String[] args) {

        Loan  l= new Loan();
        Scanner input = new Scanner(System.in);
        System.out .print("请输入贷款金额：");
        double loan=input.nextDouble();
        System.out .print("请选择贷款年限：1.3年(36个月) 2.5年(60个月)  3.20年（240个月）：");
        int yc=input.nextInt();                
        System.out.println("\n***月供为："+l.loan(loan, yc));
    }

  

public class StudentBiz {
/**
 * 求平均分
 * @param 一个学生
 */
public double getAvg(Student stu){
    return stu.java+stu.c+stu.sql/3.0;
}
public class Student {
    public int java;
    public int c;
    public int sql;

}
import java.util.Scanner;
public class Test {
public static void main(String[] args) {
    Scanner input=new Scanner(System.in);
    //实例化学生对象
            Student student=new Student();
            System.out.println("请输入java的成绩");
            student.java=input.nextInt();
            System.out.println("请输入c的成绩：");
            student.c=input.nextInt();
            System.out.println("请输入sql的成绩:");
            student.sql=input.nextInt();
            
            StudentBiz sb=new StudentBiz();
            double avgScore=sb.getAvg(student);
            System.out.println("平均分："+avgScore);
                
}
}  
public class Triangle {
    /**
     * 三角形的判断
     * @param a、b、c边长
     * @return 是否是三角形
     */
    public boolean isTriangle(int a,int b,int c){
        boolean flag=false;
        if((a+b)>c &&(b+c)>a &&(a+c)>b){
            flag=true;
        }
        return flag;
    }
    /**
     * 三角形的形状判断
     * @param a、b、c边长
     * @return 何种三角形
     */
    public String Shape(int a,int b,int c){
        String shape="";        
        
        if((a==b)&&(b==c)&&(c==a)){
            shape="等边三角形";
        }else if((a==b)||(b==c)||(c==a)){
            shape="等腰三角形";
        }else {
            int A=a*a;
            int B=b*b;
            int C=c*c;
            if((A>B+C)||(B>A+C)||(C>A+B)){
                shape="钝角三角形";
            }else if((A==B+C)||(B==A+C)||(C==A+B)){
                shape="直角三角形";
            }else{
                shape="锐角三角形";
            }
        }
        return shape;
    }

public class TestTriangle {
public static void main(String[] args) {

    Triangle t=new Triangle();
    boolean con=true;
    while(con){
        Scanner input = new Scanner(System.in);
        System.out .print("请输入第一条边：");
        int num1=input.nextInt();
        System.out .print("请输入第二条边：");
        int num2=input.nextInt();
        System.out .print("请输入第三条边：");
        int num3=input.nextInt();
        if(t.isTriangle(num1,num2,num3)){
            System.out .print("这是一个"+t.Shape(num1, num2, num3));
        }else{
            System.out .print("这不能构成三角形。");
        }
        System.out .print("\n继续吗？（y/n）:");
        String choice=input.next();
        if(choice.equals("n")){
            con=false;
            System.out .print("谢谢使用！");
        }
    }
  
public class InputVerify {
public static void main(String[] args) {
    Scanner input = new Scanner(System.in);
    boolean con = true;
    /*检验生日形式的有效性*/
    while(con){
       System.out.print("\n请输入会员生日<月/日：00/00>：  ");
       String day = input.next();
       if(day.indexOf('/')!=2){
           System.out.println("生日形式输入错误！");
       }else{
           System.out.println("该会员生日是： " + day);    
           con = false;
       }
    }
    
    con = true;
    /*检验用户密码的有效性*/
    while(con){
       System.out.print("\n请输入会员密码<6~10位>：  ");
       String psw = input.next();
       if(psw.length() < 6 || psw.length() > 10){
            System.out.println("密码形式输入错误！");
       }else{
            System.out.println("该会员的密码是： " + psw);    
            con = false;
       }
    }
}  
public class StringExplorer {
    /**
     * 定位字符
     */
    public void locateChar(String full, char c) {
        System.out.print(c + "出现的位置是： ");
        for (int i = 0; i < full.length(); i++) {
            if (c == full.charAt(i)) {
                System.out.print(i + "\t");
            }
        }
    }

    /**
     * 定位字符串
     */
    public void locateString(String full, String s) {
        int index = 0;
        int i = index;
        int length = full.length();
        System.out.print(s + "出现的位置是： ");
        do {
            index = full.indexOf(s, i);
            if (index == -1) {
                break;
            }
            System.out.print(index + "   ");
            i = index + s.length();
        } while (i <= length);
    }
 */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        StringExplorer se = new StringExplorer();
        Scanner input = new Scanner(System.in);
        System.out.println("请输入一段字符： ");
        String full = input.next();
        System.out.println("请输入要查询的字符串： ");
        String s = input.next();
        se.locateString(full, s);
    }