Rithm School Computer Science Fundamentals with JavaScript
1. Complexity Analysis and Recursion
Recursion Exercises
Part 1: Recursion Exercises
Complete the exercises here and get the tests to pass!
Part 2: Reimplementing document methods using recursion
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<div class="row main sidepane">
<h1>
<p class="row foo"></p>
<div class="row main sidepane">
<h2>
<div class="row test">1</div>
</h2>
</div>
</h1>
</div>
<div class="row">
<div class="main">
<h2 class="row">
<div id="foo" class="row main sidepane">
2
</div>
</h2>
</div>
</div>
<div class="row"></div>
</body>
</html>
- Given the following HTML, if you needed to select an element that has an ID of
foo
, you could use thedocument.getElementById
method. Try to implement that function on your own! Here are some hints:- Use helper method recursion, it will be much easier!
- In your outer function, store a variable that will either be the element found or
null
if the element can not be found. - In your inner function, iterate over an elements children and if you find the correct.
- Invoke your inner function and pass in
document.body.children
so you start from the root of the DOM.
- Given the following HTML, if you needed to select all of the elements that are a div, you could use the
document.getElementsByTagName
method. Try to implement that function on your own! Here are some hints:- The code will be VERY similar to your previous method except you will be returning an array and not checking for the same
id
, but another property.
- The code will be VERY similar to your previous method except you will be returning an array and not checking for the same
- Now given the following HTML, if you needed to select all of the elements that have a class of row, you could use the
document.getElementsByClassName
method. Try to implement that function on your own! Here are some hints:- The code will be VERY similar to your previous method except you will be checking to see if an element contains a class (research
classList
and you will find a convenient method).
- The code will be VERY similar to your previous method except you will be checking to see if an element contains a class (research
When you’re ready, move on to Dynamic Programming