You are taking the USER input only one time so i m not sure why you are using do-while loop.Also if you are trying to iterate on the basis on YES\NO then add the inputs in the do loop and add one for input about YES/NO and add this check in while.

Use below code :

public class Temperature
 {
 public static void main(String[] args){

    Scanner input = new Scanner (System.in);
    double deg;
    char dg;
    String con;

    do{
         System.out.println("Enter a number, a space and F to convert from degF to degC and C to convert to degC to degF and YES to continue");
        deg= input.nextDouble();
        String letter = input.next().toUpperCase();
        dg = letter.charAt(0);
        con = input.next();

        if( dg == 'C'){
            double cTemp= (deg-32)*5.0/9.0;
            System.out.printf("%f degC converted to degF is %.2f%n",deg, cTemp );;
        }
        else if(dg == 'F'){
            double fTemp = (deg*9/5) + 32;
            System.out.printf("%f degF converted to degC is %.2f%n",deg, fTemp );
            continue;
        }
        else{
            System.out.println("That character does not correspond to a valid unit of measure ");
            break;
        }
    }while(con.equalsIgnoreCase("YES"));
} }

thank you! i figured it out, took me a while tho.

Hola, You are close, String = response is the same as saying String the object is equal to response. That can't happen. to define a variable without giving it a value. It's as follows: ```java String response; ``` The best part of this is that because it's defined at the class level. Scope isn't a worry and you can change the value through out the class. Next, you are assuming that if I don't say No, that I am going to say yes. What if I said maybe? Then the program would fail. I didn't choose yes or no. ```java do{ response = console.readLine("Do you understand do while loops?"); }while(response.equalsIgnoreCase("no")); if{ response = "yes" console.exit; } ``` See, you have a while loop that runs 1 time no matter what. But if I choose maybe, it breaks. If I say anything other than No. It leaves the do while checks if it's yes and exits. But if it's not yes what then? ```java String response; do{ response = console.readLine("Do you understand do while loops?"); if (response.equals("No")) { console.printf("Because you said %s, you passed the test!", response); } }while(response.equals("No")); ``` Now see above. I define the variable above the do while. Now, I ask a question. IF the question comes back as No, then I print awesome you passed the test. Then it goes down to the while, and says oh sweet. It's No so it quites. Now if I typed yes, maybe, food, dog. Wouldn't matter. It would just keep going until it got No. There are several ways you could do it, you could of defined a boolean and set it in the if statement or not. But hey, less is more and do what you know. Let me know if that helps. Thanks!

Yes, but you'd want while(yn), not while(true), which goes on forever. The break only breaks from the switch statement.

---

Alright, try this:

import java.util.Scanner;

public static void main(String args[]){
  Scanner s = new Scanner(System.in);

  boolean checking = true, valid = true;
  String[] names = new String[50];
  int i = 0;

  while(checking){
    System.out.println("Enter name...");
    me = s.nextLine();
    System.out.println("You entered " + me + ".");
    while(valid){
      System.out.println("Enter another? y/n");
      you = s.nextLine();
      if(you.equals("n")){
        valid = false;
        checking = false;
      }else if you.equals("y")){
        names[i] = you;
        i++;
        valid = false;
      }else{
        System.out.println("Sorry, try again (y/n)...");
      }
    }
  }
}

I would organize this into a class with methods first. This breaks down each piece of logic and makes it easier to read.

1. Start a "play" loop
2. Inside the "play" loop, have a "guess" loop
3. Store the "continue" state in a known constant
4. Only check if they are correct after they made the max number of guesses.
5. Seed the Random object with the current system time

Also, I added a DEBUG flag to display the answer.

Update: The program is ignoring or not even asking for your "yes" input, because you were previously asking it for integers. You will need to clear/flush/reset the scanner's buffer by calling nextLine. Switching from integer to string leaves some data in the buffer. So your program will use the left-over character data in the buffer before it prompts you for your input.

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

public class HiLo implements Runnable {
    private static boolean DEBUG = true; // Disable to not show the answer...
    private static final int MAX_NUMBER = 100;
    private static final int MAX_GUESSES = 5;
    private static final String YES = "YES";

    private final Random rand;

    public HiLo() {
        this.rand = new Random(System.currentTimeMillis());
    }

    public static void main(String[] args) {
        new Thread(new HiLo()).start();
    }

    @Override
    public void run() {
        Scanner scan = new Scanner(System.in);
        String cont = "";
        do {
            play(scan);
            System.out.print("\nWould you like to play again (yes/no)? ");
            cont = scan.nextLine();
            System.out.println();
        } while (cont.equalsIgnoreCase(YES));
        scan.close();
    }

    public void play(Scanner scan) {
        boolean correct = false;
        int numberOfGuesses = 0;
        int answer = rand.nextInt(MAX_NUMBER) + 1;

        if (DEBUG) System.out.printf("The answer is: %d%n", answer);

        System.out.printf("Guess a number between 1 and %d%n", MAX_NUMBER);

        while (numberOfGuesses < MAX_GUESSES && !correct) {
            numberOfGuesses++;
            correct = makeGuess(scan, answer, numberOfGuesses);
        }

        if (numberOfGuesses <= MAX_GUESSES && correct) {
            System.out.printf("Correct! The number was %d. It took you %d guesses.%n", answer, numberOfGuesses);
        } else {
            System.out.printf("Sorry, but you did not guess: %d", answer);
        }
        scan.nextLine(); // Reset...
    }

    public boolean makeGuess(Scanner scan, int answer, int currentGuesses) {
        System.out.print("Guess: ");
        int guess = scan.nextInt();

        if (guess == answer) {
            return true;
        }

        if (currentGuesses < MAX_GUESSES) {
            if (guess > answer) {
                System.out.print("Too High, ");
            } else {
                System.out.print("Too Low, ");
            }
        }

        return false;
    }
}

Sample Output

The answer is: 64
Guess a number between 1 and 100
Guess: 50
Too Low, Guess: 75
Too High, Guess: 60
Too Low, Guess: 65
Too High, Guess: 64
Correct! The number was 64. It took you 5 guesses.

Would you like to play again (yes/no)? yes

The answer is: 88
Guess a number between 1 and 100
Guess: 50
Too Low, Guess: 90
Too High, Guess: 80
Too Low, Guess: 85
Too Low, Guess: 87
Sorry, but you did not guess: 88

Would you like to play again (yes/no)? no

You need to use .equals() in the while loop conditions because you're comparing strings. So while(!answer.equals("Yes") && !answer.equals("No")) Edit: Okay a few other things I noticed: you don't have a closing bracket on line 4 for the while loop which might be the reason you're seeing Invalid Input. You're using printf on line 13, which really isn't necessary considering you're not using formatting. I would use print or println instead. You would use printf if your output was ("blah blah blah %f blah blah blah", doubleVal) You haven't initialized defaultTaxRate to any value outside of the else, might want to fix that.

Where it says '"Do you wish to continue? (yes/no)" @ line #24, when entered "Yes", how can I make it so my program loops the entire program? Help would be highly appreciated, sooner than later if possible :d

The issue is that you are checking only the first letter of the read string:

char response = keyboard.next().charAt(0)

You should read the whole string:

String response = keyboard.next()

And use it in the comparison. In order to ensure that also 'Y' and 'N' are considered valid, you can use the String.equalsIgnoreCase(String):

while (!"Y".equalsIgnoreCase(response) && "N".equalsIgnoreCase(response))

System.out.println("\nWould you like to order some coffee, " + customerName + "? (y/n)");

So, wrapping all together this would look like this:

String response = keyboard.next();

while (!"Y".equalsIgnoreCase(response) && "N".equalsIgnoreCase(response)) {
   System.out.println("\nInvalid response. Try again.");
   response = keyboard.next();
} 

if ("N".equalsIgnoreCase(response)) {
   System.out.println("\nCome back next time, " + customerName + ".");
} else if ("Y".equalsIgnoreCase(response)) {
   System.out.println("\nGreat! Let's get started.");
}

Put your code that computes your magic square in a separate method, and have your input reading code in a while loop, that calls that method until the user presses N, for example.