Thread: Play again not working !

Hi tonynsx, welcome to the forums!

I have added code tags to your post. You put [code] at the start of a section of code, and [/code] at the end. That way the code will be formatted properly by the forum software and will be readable.

It would help if you explained what the problem is. Rather than "not working", say what happens when you run the program and give it specific input.

Thank you,

The problem is, every thing is working as I want, except when it asks "Play again? (y/n)". It asks that question, but it would not let me type in the response (y/n).

Well the program is definitely assigning *some* value to playAgain. You can add some code to see what value is being assigned to that variable.

System.out.println("Play again? (y/n)");
playAgain = scan.nextLine();
System.out.println("playAgain set to -->" + playAgain + "<--");

The reason for the little arrows is to make it very clear what the value of playAgain is: including an empty string or a string with whitespace in it.

---

To see why you get the output you get with this code have a careful read of the documentation for the two Scanner methods you use: nextInt() and nextLine().

This is the program with modification, and to see what "playAgain" is set to. Still, it won't let me type in a value when it asks PlayAgain.

/*
 * Design and implement an application that plays the Hi-Lo guessing
 * game with numbers.  The program should pick a random number
 * between 1 and 100, and then repeatedly prompt the
 * user to guess the number.  On each guess, report to the user that
 * he/she is correct or that the guess is too high or low.  Continue 
 * accepting guesses until the user guess correctly or quits.  At the end 
 * of the game, ask the user if he/she wants to play again.
 */
 
package chapterFour;
 
import java.util.Scanner;
import java.util.Random;
 
public class problem8 {
 
	public static void main(String[] args) {
 
		Scanner scan = new Scanner(System.in);
 
		Random rand = new Random();
 
		String playAgain = "n";
 
		int num = 0, randomNumber, guesses = 0;
 
		randomNumber = rand.nextInt(100) + 1;
 
		while(playAgain.equalsIgnoreCase("y"));
 
		{
 
		while(num != randomNumber)
		{
			System.out.print("Enter a random number between 1 and 100 to guess : ");
			num = scan.nextInt();			
 
			if(num > randomNumber)
				System.out.println("Too high");
 
			if(num < randomNumber)
				System.out.println("Too low");
 
			else if(num == randomNumber)
				System.out.print("Correct, ");
 
			guesses++;
		}
 
		System.out.println("It took you " + guesses + " guesses to get it! ");	
 
		System.out.println("Play again? (y/n)");
		playAgain = scan.nextLine();
		System.out.println("Play again set to -----> " + playAgain + " <-----");
 
	}
 
	}
 
}

Enter a random number between 1 and 100 to guess : 67
Too high
Enter a random number between 1 and 100 to guess : 45
Too low
Enter a random number between 1 and 100 to guess : 55
Too high
Enter a random number between 1 and 100 to guess : 50
Too low
Enter a random number between 1 and 100 to guess : 52
Too high
Enter a random number between 1 and 100 to guess : 51
Correct, It took you 6 guesses to get it! 
Play again? (y/n)
Play again set to ----->  <-----

--- Update ---

Here, I've made playAgain an int instead of a string, now it's asking if I want to play again, but if I press 1 or 0, it won't do anything

/*
 * Design and implement an application that plays the Hi-Lo guessing
 * game with numbers.  The program should pick a random number
 * between 1 and 100, and then repeatedly prompt the
 * user to guess the number.  On each guess, report to the user that
 * he/she is correct or that the guess is too high or low.  Continue 
 * accepting guesses until the user guess correctly or quits.  At the end 
 * of the game, ask the user if he/she wants to play again.
 */
 
package chapterFour;
 
import java.util.Scanner;
import java.util.Random;
 
public class problem8 {
 
	public static void main(String[] args) {
 
		Scanner scan = new Scanner(System.in);
 
		Random rand = new Random();
 
		int playAgain = 1;
 
		int num = 0, randomNumber, guesses = 0;
 
		randomNumber = rand.nextInt(100) + 1;
 
		while(playAgain != 1);
 
		{
 
		while(num != randomNumber)
		{
			System.out.print("Enter a random number between 1 and 100 to guess : ");
			num = scan.nextInt();			
 
			if(num > randomNumber)
				System.out.println("Too high");
 
			if(num < randomNumber)
				System.out.println("Too low");
 
			else if(num == randomNumber)
				System.out.print("Correct, ");
 
			guesses++;
		}
 
		System.out.println("It took you " + guesses + " guesses to get it! ");	
 
		System.out.print("Play again? (1 to continue, 0 to quit)) ");
		playAgain = scan.nextInt();
		System.out.println("Play again set to -----> " + playAgain + " <-----");
 
	}
 
	}
 
}

Enter a random number between 1 and 100 to guess : 54
Too low
Enter a random number between 1 and 100 to guess : 78
Too low
Enter a random number between 1 and 100 to guess : 89
Too low
Enter a random number between 1 and 100 to guess : 94
Too low
Enter a random number between 1 and 100 to guess : 96
Too high
Enter a random number between 1 and 100 to guess : 95
Correct, It took you 6 guesses to get it! 
Play again? (1 to continue, 0 to quit)) 1
Play again set to -----> 1 <-----

Made those changes, now it asks, and accepts (y/n) for answer, but still won't play again if I select 'y'

/*
 * Design and implement an application that plays the Hi-Lo guessing
 * game with numbers.  The program should pick a random number
 * between 1 and 100, and then repeatedly prompt the
 * user to guess the number.  On each guess, report to the user that
 * he/she is correct or that the guess is too high or low.  Continue 
 * accepting guesses until the user guess correctly or quits.  At the end 
 * of the game, ask the user if he/she wants to play again.
 */
 
package chapterFour;
 
import java.util.Scanner;
import java.util.Random;
 
public class problem8 {
 
	public static void main(String[] args) {
 
		Scanner scan = new Scanner(System.in);
 
		Random rand = new Random();
 
		String playAgain = "n";
 
		int num = 0, randomNumber, guesses = 0;
 
		randomNumber = rand.nextInt(100) + 1;
 
		while(playAgain.equalsIgnoreCase("y"));
 
		{
 
		while(num != randomNumber)
		{
			System.out.print("Enter a random number between 1 and 100 to guess : ");
			num = scan.nextInt();			
 
			if(num > randomNumber)
				System.out.println("Too high");
 
			if(num < randomNumber)
				System.out.println("Too low");
 
			else if(num == randomNumber)
				System.out.print("Correct, ");
 
			guesses++;
		}
 
		System.out.println("It took you " + guesses + " guesses to get it! ");	
 
		if(scan.hasNextLine())
		{
			scan.nextLine();
			System.out.print("Play again? (y/n) ");
			playAgain = scan.nextLine();
			System.out.println("Play again set to -----> " + playAgain + " <-----");
		}	
 
 
	}
 
	}
 
}

Enter a random number between 1 and 100 to guess : 34
Too high
Enter a random number between 1 and 100 to guess : 20
Too low
Enter a random number between 1 and 100 to guess : 25
Too low
Enter a random number between 1 and 100 to guess : 30
Too low
Enter a random number between 1 and 100 to guess : 32
Too high
Enter a random number between 1 and 100 to guess : 31
Correct, It took you 6 guesses to get it!
Play again? (y/n) y
Play again set to -----> y <-----

Thank you, I've removed the semicolon, and it's looping. I didn't know having a ; would not let it loop.

--- Update ---

Now, it's looping and asking if I want to play again, but it' s only looping my "It took you ----- guesses to get it part.

--- Update ---

/*
 * Design and implement an application that plays the Hi-Lo guessing
 * game with numbers.  The program should pick a random number
 * between 1 and 100, and then repeatedly prompt the
 * user to guess the number.  On each guess, report to the user that
 * he/she is correct or that the guess is too high or low.  Continue 
 * accepting guesses until the user guess correctly or quits.  At the end 
 * of the game, ask the user if he/she wants to play again.
 */
 
package chapterFour;
 
import java.util.Scanner;
import java.util.Random;
 
public class problem8 {
 
	public static void main(String[] args) {
 
		Scanner scan = new Scanner(System.in);
 
		Random rand = new Random();
 
		String playAgain = "y";
 
		int num = 0, randomNumber, guesses = 0;
 
		randomNumber = rand.nextInt(10) + 1;
 
		while(playAgain.equalsIgnoreCase("y"))
 
		{
 
		while(num != randomNumber)
		{
			System.out.print("Enter a random number between 1 and 10 to guess : ");
			num = scan.nextInt();			
 
			if(num > randomNumber)
				System.out.println("Too high");
 
			if(num < randomNumber)
				System.out.println("Too low");
 
			else if(num == randomNumber)
				System.out.print("Correct, ");
 
			guesses++;
		}
 
		System.out.println("It took you " + guesses + " guesses to get it! ");	
 
		if(scan.hasNextLine())
		{
			scan.nextLine();
 
			System.out.print("Play again? (y/n) ");
			playAgain = scan.nextLine();
		}	
 
	}
 
	}
 
}

The semi-colon at the end of the first while statement ends the while statement - the while loop - so it will loop, but only between the while( condition ) and the semi-colon, effectively not looping at all.

For your latest complaint, look at the second while loop and consider what must be done to reinitialize the loop control variables (or the loop condition) so that the game will play again. For instance, isn't a new random number required?