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JavaScript JavaScript Loops, Arrays and Objects Simplify Repetitive Tasks with Loops The Refactor Challenge

sorin vasiliu
sorin vasiliu
6,228 Points
Posted by sorin vasiliu
sorin vasiliu
6,228 Points

refactor challenge quickie quick question

Hey guy! Why do I have to make i < 4 in order to print out 10 colors ? what did I do wrong in the code ? 

var html = '';
var red;
var green;
var blue;
var rgbColor;


function randomColor() {
  red = Math.floor(Math.random() * 256 );
  green = Math.floor(Math.random() * 256 );
  blue = Math.floor(Math.random() * 256 );
  rgbColor = 'rgb(' + red + ',' + green + ',' + blue + ')';
  html += '<div style="background-color:' + rgbColor + '"></div>';
  document.write(html);
}

for ( var i = 0; i < 4; i++ ) {
  randomColor();
}

As a result, this prints out 10 color bubbles. Why? I don't get why it adds up to 10... Thanks!

1 Answer

Daniel Newman
Daniel Newman
Courses Plus Student 10,715 Points

What you do is "factorial". Look:

function randomColor() {
  html += '<div style="background-color:' + rgbColor + '"></div>';
  document.write(html);
}

for ( var i = 0; i < 4; i++ ) {
  randomColor();
}

Your html for times (html = html + newone): yourloop { html = html + newone; }

It will be

html = html + newone

html = ( html + newone ) + newone

html = ( html + newone + newone ) + newone

html = ( html + newone + newone + newone ) + newone

html = ( html + newone + newone + newone + newone ) + newone

You can put console.log(html) inside your loop to see how it happens.

sorin vasiliu
sorin vasiliu
6,228 Points
sorin vasiliu
sorin vasiliu
6,228 Points

Yup! I see it now! Thank you for the good inside!