于9.28做出修改

import java.util.*;
public class guessnum {
static Scanner sc = new Scanner(System.in);
public static void main(String[] args) {
Random num= new Random();
System.out.println("\n"+"\n"+"\t"+"欢迎来到猜数小世界，我是小宇");
System.out.print("请输入你要猜的数的上限:");

int limit=sc.nextInt();
int nonce=num.nextInt(limit);
double p;
for(int i=1;;i++){
System.out.print("\t"+"    "+"请输入您猜测的数:");
int guess=sc.nextInt();
if(guess==nonce){
    p=(1.0/i)*100;
System.out.println("恭喜你,终于猜对了,您一共猜了"+i+"次,本次准确率为:"+p+"%");
break;
}
else
if(guess<nonce)
System.out.println("\t"+"\t"+"          "+"猜小了");
else 
System.out.println("\t"+"\t"+"          "+"猜大了");
}
sc.close();
}
}

刚学java时所做，不喜勿喷