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

Posted by Björn Wauben
Björn Wauben
10,748 Points

Rewriting While loop into Do...while loop

After I had some trouble with the original challenge of this while loop I finally passed the challenge. In another challenge I need to rewrite this while loop into a do..while loop.

I tried breaking it down into steps. I should write a "statement" which executes at least once as long as the condition is true. So I think I need to use prompt in the statement and test if the password is not equal to "sesame" in the condition so the loop runs untill the condition is false and matches "sesame" Is this thought-process correct?

if so I might have trouble with the syntax and that's why it doesn't pass the challenge.

(note: I left the original code as an example when I tried to pass the challnge I only have the do...while loop in the window)

script.js 
var secret = prompt("What is the secret password?");
while ( secret !== "sesame" ) {
  secret = prompt("What is the secret password?");    
}
document.write("You know the secret password. Welcome.");



do { secret = prompt("What is the secret password?");
   }
while (secret !== "sesame")

  document.write("You know the secret password. Welcome.");
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

2 Answers

Jonathan Söder
Jonathan Söder
7,428 Points

ah! 

var secret;
do { 
   secret = prompt("What is the secret password?");
   }
while (secret !== "sesame")

  document.write("You know the secret password. Welcome.");

You need to declare the variable secret outside of the loop, but don't add any value to it. then you call it inside the loop, like above

Björn Wauben
Björn Wauben
10,748 Points

Thanks. It works. Glad at least the loop part was oké.

Jonathan Söder
Jonathan Söder
7,428 Points
Jonathan Söder
Jonathan Söder
7,428 Points

does it work when you add a semicolon at the end of the while? Or is it something else entirely?

Björn Wauben
Björn Wauben
10,748 Points

No is says: "You only need to call the prompt() method once, and only inside the loop." But I think I do this. I tried to remove the variable but then it says that I need to declare it outside the loop.