一，教材上的代码:

import java.util.Scanner;
import java.util.Random;
public class GuessNumber{
          
   
	public static void main(String args[]){
          
   
		Scanner reader = new Scanner(System.in);
		Random random=new Random();
		System.out.println("给你一个1至100之间的整数,请猜测这个数:");
		int realNumber=random.nextInt(100)+1;//random.nextInt(100)是[0,100)中的随机整数
		int yourGuess=0;
		System.out.print("请输入你的猜测:");
		yourGuess=reader.nextInt();
		while(yourGuess != realNumber)//循环条件
		{
          
   
			if(yourGuess>realNumber)//猜大了的条件代码
			{
          
   
				System.out.print("猜大了,再输入你的猜测:");
				yourGuess=reader.nextInt();
			}
			else if (yourGuess<realNumber)//猜小了的条件代码
			{
          
   
				System.out.print("猜小了，再输入你的代码:");
				yourGuess=reader.nextInt();
			}
		}
		System.out.print("猜对了！");
	}
}

二，优化用户体验代码(提示区间,运气值判定):

import java.util.Scanner;
import java.util.Random;
public class GuessNumberS{
          
   
	public static void main(String args[]){
          
   
		Scanner reader = new Scanner(System.in);
		Random random=new Random();
		System.out.println("给你一个1至100之间的整数,请猜测这个数:[1,100]");
		int realNumber=random.nextInt(100)+1;//random.nextInt(100)是[0,100)中的随机整数
		int yourGuess=0,count=0;
		int high=100,low=1;
		System.out.print("请输入你的猜测:");
		yourGuess=reader.nextInt();
		count++;
		while(yourGuess != realNumber)//循环条件
		{
          
   
			if(yourGuess>realNumber)//猜大了的条件代码
			{
          
   
				high=yourGuess;
				System.out.println("猜大了,再输入你的猜测["+low+","+high+"]");
				yourGuess=reader.nextInt();
				count++;
			}
			else if (yourGuess<realNumber)//猜小了的条件代码
			{
          
   
				low=yourGuess;
				System.out.println("猜小了，再输入你的猜测["+low+","+high+"]");
				yourGuess=reader.nextInt();
				count++;
			}
		}
		switch(count){
          
   
			case 1:	System.out.print("你一下就猜到了，你一定是天选之人！");	break;
		}
		if(count>1 && count<=5){
          
   
			System.out.print("你只猜了"+count+"次就猜对啦！！！你的运气太好啦！");
		}else if(count>5 && count<=8){
          
   
			System.out.print("你一共猜了"+count+"次！！也很棒呦~");
		}else if(count>8 && count<=10000){
          
   
			System.out.print("你一共猜了"+count+"次！");
		}
	}
}