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Thread: Do-While Loop Help

  1. #1
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    Exclamation Do-While Loop Help

    My code keeps showing me an error and saying that my "redo" in the end part of my do while loop the symbol is not found.

    I want to be able to ask if the user would like to repeat this random number guessing and if they say "y" or "Y" then it produces anoter random number & repeats the program!

    Help please what is wrong..???

    package mylab;
    import javax.swing.JOptionPane;
     
    public class MyLab {
     
        public static void main(String[] args) {
     
            do {
            int random;
            int guess;
            String redo;
     
            random = (int)((Math.random()* 9 + 1));
            System.out.println("The random number is: " + random);
     
            // Prompt user to enter a guess for the number
            JOptionPane.showMessageDialog(null, "I have a secret number, can you guess what it is?");
     
            do {
            String stringOne = JOptionPane.showInputDialog("Guess the number: ");
            guess = Integer.parseInt(stringOne);
     
            if (guess < random)
                JOptionPane.showMessageDialog(null, "To small, try again!!!!");
     
            else if (guess > random)
                JOptionPane.showMessageDialog(null, "Too large, try again!!!");
     
            else if (guess == random)
                redo = JOptionPane.showInputDialog(null, "Bingo! Another try? (Y/N)");
     
            } while (guess != random);
     
            } while (redo == "Y" || redo == "y");
        } 
     
    }

  2. #2
    Member John Joe's Avatar
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    Default Re: Do-While Loop Help

    You are declaring the redo inside the do , so you will get symbol is not found error. You should declare redo outside the do.

     public static void main(String[] args) {
            String redo = null; // declare and initialize it
            do {
            int random;
            int guess;
              .......
             }
    Whatever you are, be a good one

  3. #3
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    Default Re: Do-While Loop Help

    Quote Originally Posted by John Joe View Post
    You are declaring the redo inside the do , so you will get symbol is not found error. You should declare redo outside the do.

     public static void main(String[] args) {
            String redo = null; // declare and initialize it
            do {
            int random;
            int guess;
              .......
             }
    Yeah but when I try that when I type "Y" in the input for if I'd like to run the program again it just ends the program after that and does not repeat the program.. it's not doing the "do" part of the do while loop even though my while says if redo = "Y" or "y".

  4. #4
    Member John Joe's Avatar
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    Default Re: Do-While Loop Help

    when I type "Y" in the input for if I'd like to run the program again it just ends the program after that and does not repeat the program
    Use equals instead of == .

    while (redo.equals( "Y") || redo.equals( "y"))
    Whatever you are, be a good one

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    Super Moderator Norm's Avatar
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    Default Re: Do-While Loop Help

    Also there is a String method that will compare Strings ignoring the case that would simplify that statement a bit.
    If you don't understand my answer, don't ignore it, ask a question.

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