为什么这段代码会打印出无数的“您的猜测是什么？”

Question

I'm trying to make a number guessing game between the range from 1 to 100. The program will stop if the user guesses the correct number.

My current code:

import java.util.Scanner;
import java.util.Random;

public class GuessingGame {
    public static void main(String[] args) {
        Random randomNumber = new Random();
        Scanner reader = new Scanner(System.in);
        System.out.println("What's your guess? ");
        int n = reader.nextInt();
        reader.close();

    int Number = randomNumber.nextInt(100 + 1);
    int guess = n;
     while (guess != Number) {
        System.out.println("What's your guess? ");
        new Scanner(System.in);
    }

    if (guess == Number) {
        System.out.println("Your have guessed the correct number! ");
    }

    else if (guess < Number) {
        System.out.println("Your number is too low! ");
    }

    else if (guess > Number) {
        System.out.println("Your number is too high! ");
    }
}   
}            

Answer 1

This is where using the formatter in your IDE is helpful. You would be able to see that the if conditions which are after the loop should be inside the loop and you should be reading the reading the guess from input.

BTW You should never close the input unless you explicitly don't want to read anything from it ever again.

try

 Random randomNumber = new Random();
 Scanner reader = new Scanner(System.in);
 int number = randomNumber.nextInt(100 + 1);
 while(true) {
    System.out.println("What's your guess? ");
    int guess = reader.nextInt();

    if (guess == Number) {
        System.out.println("You have guessed the correct number! ");
        break; // no need to guess more

    } else if (guess < Number) {
        System.out.println("Your number is too low! ");

    } else if (guess > Number) {
        System.out.println("Your number is too high! ");
    }
}   

Answer 2

Change your while loop to

while (guess != Number) {
    if (guess == Number) {
     System.out.println("Your have guessed the correct number! ");
     break;
    }

    else if (guess < Number) {
     System.out.println("Your number is too low! ");
    }

    else if (guess > Number) {
     System.out.println("Your number is too high! ");
    }

    System.out.println("Guess Again?");
    guess = reader.nextInt();
}

Answer 3

The while loop is infinite loop. Also, you should avoid using 'Number' as variable name as there is a class in java with the same name java.lang.Number . You can also need any number of variables using single object of Scanner class. So, a cleaner code would look like this :

while (guess != number) {
        System.out.println("What's your guess? ");
        guess = reader.nextInt();
    }

Now, if you solve above problems, your code will never go to the two else-if blocks, because by the time your while loop breaks you will have 'guess' always be equal to 'number'. I think what you are trying to achieve here is :

while (guess != number) {
    System.out.println("What's your guess? ");
    guess = reader.nextInt();

    if (guess == number) {
        System.out.println("Your have guessed the correct number! ");
    }

    else if (guess < number) {
        System.out.println("Your number is too low! ");
    }

    else if (guess > number) {
        System.out.println("Your number is too high! ");
    }
}