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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops `do ... while` Loops

Posted by Harcharan Riyait
Harcharan Riyait
1,625 Points

Do While loop in endless loop

I have tried following along in the Do...While lesson, but when previewing the code, it keeps looping over and over. Can anyone see what I am doing wrong?

Thanks in advance

<script>
var randomNumber = getRandomNumber(10);
var guess;
var guessCount = 0;
var correctGuess = false;

function getRandomNumber( upper ) {
  var num = Math.floor(Math.random() * upper) + 1; 
  return num;
}

do {
  guess = prompt("I am thinking of a number between 1 and 10. What is it?");
  guessCount += 1;
  if(parseInt(guess) === randomNumber){
    correctGuess = true;
  }
} while( ! correctGuess )
  document.write("<h1>You guessed the number!</h1>");
  document.write("It took you " + guessCount + " tries to guess the correct number " + randomNumber);
</script>
Pier Yos
Pier Yos
15,721 Points
Pier Yos
Pier Yos
15,721 Points

It stops when you enter the correct number. It worked fine when i tested.

rydavim
rydavim
18,814 Points
rydavim
rydavim
18,814 Points

Can you elaborate on the problem you're encountering? Your code seems to be working correctly for me.

3 Answers

Stephen Layton
Stephen Layton
8,643 Points
Stephen Layton
Stephen Layton
8,643 Points

It doesn't look like your calling the getRandomNumber function. Adding a randomNumber variable above your do should do the trick.

function getRandomNumber( upper ) {
  var num = Math.floor(Math.random() * upper) + 1; 
  return num;
}

var randomNumber = getRandomNumber(10);

do {
  guess = prompt("I am thinking of a number between 1 and 10. What is it?");
  guessCount += 1;
Harcharan Riyait
Harcharan Riyait
1,625 Points
Harcharan Riyait
Harcharan Riyait
1,625 Points

@Stephen Layton: Isn't the getRandomNumber called at the top of the script?

i am confused because this is the code from the lesson. It's stopped me dead on the loops section because I don't uunderstand why it gets stuck in the loop. I have looked for a line I may have missed when following along, but can't see it.

@rydavim: The loop carries on over and over asking for the random number. I try each number from 1 through 10 but none work.

Again, this is the code from the lesson as close as I could match it.

Harcharan Riyait
Harcharan Riyait
1,625 Points
Harcharan Riyait
Harcharan Riyait
1,625 Points

Ok, so I threw the code into JSBin and now it reaches the end with the 'correct number' message regardless of the number I input. I could input 1 over and over and it will still end saying that I guessed the correct number 8 or 5 or 7, etc.

So confused!

Iain Simmons
Iain Simmons
Treehouse Moderator 32,305 Points

Can you open the JavaScript console and report back any errors you're getting in either case?

Alternatively, you can 'watch' the value of the variables within the function by adding a breakpoint in the sources tab of the dev tools (if using Chrome), but that's a little more advanced.