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

Chris Carr
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Chris Carr
Front End Web Development Techdegree Student 12,900 Points
Posted by Chris Carr
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Chris Carr
Front End Web Development Techdegree Student 12,900 Points

Do While Loop Alternative Code

var randomNumber = getRandomNumber(10);
var guess;
var guessCount = 0;

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

do {
 guess = prompt ("Guess a number from 1 to 10");
 guess = parseInt(guess);
 guessCount += 1 ; 
} while (guess !== randomNumber);

document.write("<p>You guessed correctly! " + randomNumber + " is the correct number.</p>");
document.write("<p>You guessed " + guessCount + " number of times.</p>");

Does my code do the job? Or will I need a conditional statement like in the video?

2 Answers

Stephan Olsen
Stephan Olsen
6,650 Points
Stephan Olsen
Stephan Olsen
6,650 Points

Your code does the job and is perfectly valid. When coding, there are various ways to complete the task you're doing. How you write the code comes down to preference.

Devjyoti Ghosh
Devjyoti Ghosh
2,422 Points
Devjyoti Ghosh
Devjyoti Ghosh
2,422 Points

Why is there a semicolon after the do while loop? Shouldn't it give a syntax error?

Chris Carr
seal-mask
.a{fill-rule:evenodd;}techdegree
Chris Carr
Front End Web Development Techdegree Student 12,900 Points
Chris Carr
.a{fill-rule:evenodd;}techdegree
Chris Carr
Front End Web Development Techdegree Student 12,900 Points

It is the correct syntax. The semi colon comes after the closing parentheses in the while condition. The do while loop is different other loops as it is the only one that requires a semi colon. Someone correct me if I'm wrong.

Devjyoti Ghosh
Devjyoti Ghosh
2,422 Points
Devjyoti Ghosh
Devjyoti Ghosh
2,422 Points

From what I could find online in Javascript semicolon after do while seems to be a styling choice and is optional. In other languages like c++ and java it is required. Source