fix: added all js to end of 3 backticks

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/-iterate-through-the-keys-of-an-object-with-a-for...in-statement.english.md

@@ -19,7 +19,6 @@ Jeff
 Sarah
 Ryan
 ```
-
 In this statement, we defined a variable <code>user</code>, and as you can see, this variable was reset during each iteration to each of the object's keys as the statement looped through the object, resulting in each user's name being printed to the console.
 <strong>NOTE:</strong> Objects do not maintain an ordering to stored keys like arrays do; thus a key's position on an object, or the relative order in which it appears, is irrelevant when referencing or accessing that key.
 </section>
@@ -28,18 +27,20 @@ In this statement, we defined a variable <code>user</code>, and as you can see,
 <section id='instructions'>
 We've defined a function <code>countOnline</code> which accepts one argument (a users object). Use a <dfn>for...in</dfn> statement within this function to loop through the users object passed into the function and return the number of users whose <code>online</code> property is set to <code>true</code>.  An example of a users object which could be passed to <code>countOnline</code> is shown below.  Each user will have an <code>online</code> property with either a <code>true</code> or <code>false</code> value.
 
-<blockquote>
-{<br>
-&nbsp;&nbsp;Alan: {<br>
-&nbsp;&nbsp;&nbsp;&nbsp;online: false<br>
-&nbsp;&nbsp;},<br>
-&nbsp;&nbsp;Jeff: {<br>
-&nbsp;&nbsp;&nbsp;&nbsp;online: true<br>
-&nbsp;&nbsp;},<br>
-&nbsp;&nbsp;Sarah: {<br>
-&nbsp;&nbsp;&nbsp;&nbsp;online: false<br>
-&nbsp;&nbsp;}<br>
-}</blockquote>
+
+```js
+{
+  Alan: {
+    online: false
+  },
+  Jeff: {
+    online: true
+  },
+  Sarah: {
+    online: false
+  }
+}
+```
 </section>
 
 ## Tests

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/access-an-arrays-contents-using-bracket-notation.english.md

@@ -24,7 +24,7 @@ let ourVariable = ourArray[0];
 
 In addition to accessing the value associated with an index, you can also <em>set</em> an index to a value using the same notation:
 
-```
+```js
 ourArray[1] = "not b anymore";
 // ourArray now equals ["a", "not b anymore", "c"];
 ```

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/access-property-names-with-bracket-notation.english.md

@@ -8,7 +8,7 @@ challengeType: 1
 <section id='description'>
 In the first object challenge we mentioned the use of bracket notation as a way to access property values using the evaluation of a variable. For instance, imagine that our <code>foods</code> object is being used in a program for a supermarket cash register. We have some function that sets the <code>selectedFood</code> and we want to check our <code>foods</code> object for the presence of that food. This might look like:
 
-```
+```js
 let selectedFood = getCurrentFood(scannedItem);
 let inventory = foods[selectedFood];
 ```

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/add-items-to-an-array-with-push-and-unshift.english.md

@@ -9,7 +9,7 @@ challengeType: 1
 An array's length, like the data types it can contain, is not fixed. Arrays can be defined with a length of any number of elements, and elements can be added or removed over time; in other words, arrays are <dfn>mutable</dfn>. In this challenge, we will look at two methods with which we can programmatically modify an array: <code>Array.push()</code> and <code>Array.unshift()</code>.
 Both methods take one or more elements as parameters and add those elements to the array the method is being called on; the <code>push()</code> method adds elements to the end of an array, and <code>unshift()</code> adds elements to the beginning. Consider the following:
 
-```
+```js
 let twentyThree = 'XXIII';
 let romanNumerals = ['XXI', 'XXII'];
 

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/add-items-using-splice.english.md

@@ -8,7 +8,7 @@ challengeType: 1
 <section id='description'>
 Remember in the last challenge we mentioned that <code>splice()</code> can take up to three parameters? Well, we can go one step further with <code>splice()</code> &mdash; in addition to removing elements, we can use that third parameter, which represents one or more elements, to <em>add</em> them as well. This can be incredibly useful for quickly switching out an element, or a set of elements, for another. For instance, let's say you're storing a color scheme for a set of DOM elements in an array, and want to dynamically change a color based on some action:
 
-```
+```js
 function colorChange(arr, index, newColor) {
   arr.splice(index, 1, newColor);
   return arr;

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/add-key-value-pairs-to-javascript-objects.english.md

@@ -8,7 +8,7 @@ challengeType: 1
 <section id='description'>
 At their most basic, objects are just collections of <dfn>key-value pairs</dfn>, or in other words, pieces of data mapped to unique identifiers that we call <dfn>properties</dfn> or <dfn>keys</dfn>. Let's take a look at a very simple example:
 
-```
+```js
 let FCC_User = {
   username: 'awesome_coder',
   followers: 572,
@@ -19,14 +19,14 @@ let FCC_User = {
 
 The above code defines an object called <code>FCC_User</code> that has four <dfn>properties</dfn>, each of which map to a specific value. If we wanted to know the number of <code>followers</code> <code>FCC_User</code> has, we can access that property by writing:
 
-```
+```js
 let userData = FCC_User.followers;
 // userData equals 572
 ```
 
 This is called <dfn>dot notation</dfn>. Alternatively, we can also access the property with brackets, like so:
 
-```
+```js
 let userData = FCC_User['followers']
 // userData equals 572
 ```

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/check-for-the-presence-of-an-element-with-indexof.english.md

@@ -9,7 +9,7 @@ challengeType: 1
 Since arrays can be changed, or <em>mutated</em>, at any time, there's no guarantee about where a particular piece of data will be on a given array, or if that element even still exists. Luckily, JavaScript provides us with another built-in method, <code>indexOf()</code>, that allows us to quickly and easily check for the presence of an element on an array. <code>indexOf()</code> takes an element as a parameter, and when called, it returns the position, or index, of that element, or <code>-1</code> if the element does not exist on the array.
 For example:
 
-```
+```js
 let fruits = ['apples', 'pears', 'oranges', 'peaches', 'pears'];
 
 fruits.indexOf('dates') // returns -1

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/check-if-an-object-has-a-property.english.md

@@ -8,7 +8,7 @@ challengeType: 1
 <section id='description'>
 Now we can add, modify, and remove keys from objects. But what if we just wanted to know if an object has a specific property? JavaScript provides us with two different ways to do this. One uses the <code>hasOwnProperty()</code> method and the other uses the <code>in</code> keyword. If we have an object <code>users</code> with a property of <code>Alan</code>, we could check for its presence in either of the following ways:
 
-```
+```js
 users.hasOwnProperty('Alan');
 'Alan' in users;
 // both return true

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/combine-arrays-with-the-spread-operator.english.md

@@ -8,7 +8,7 @@ challengeType: 1
 <section id='description'>
 Another huge advantage of the <dfn>spread</dfn> operator, is the ability to combine arrays, or to insert all the elements of one array into another, at any index. With more traditional syntaxes, we can concatenate arrays, but this only allows us to combine arrays at the end of one, and at the start of another. Spread syntax makes the following operation extremely simple:
 
-```
+```js
 let thisArray = ['sage', 'rosemary', 'parsley', 'thyme'];
 
 let thatArray = ['basil', 'cilantro', ...thisArray, 'coriander'];

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/copy-an-array-with-the-spread-operator.english.md

@@ -9,7 +9,7 @@ challengeType: 1
 While <code>slice()</code> allows us to be selective about what elements of an array to copy, among several other useful tasks, ES6's new <dfn>spread operator</dfn> allows us to easily copy <em>all</em> of an array's elements, in order, with a simple and highly readable syntax. The spread syntax simply looks like this: <code>...</code>
 In practice, we can use the spread operator to copy an array like so:
 
-```
+```js
 let thisArray = [true, true, undefined, false, null];
 let thatArray = [...thisArray];
 // thatArray equals [true, true, undefined, false, null]

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/copy-array-items-using-slice.english.md

@@ -8,7 +8,7 @@ challengeType: 1
 <section id='description'>
 The next method we will cover is <code>slice()</code>. <code>slice()</code>, rather than modifying an array, copies, or <em>extracts</em>, a given number of elements to a new array, leaving the array it is called upon untouched. <code>slice()</code> takes only 2 parameters &mdash; the first is the index at which to begin extraction, and the second is the index at which to stop extraction (extraction will occur up to, but not including the element at this index). Consider this:
 
-```
+```js
 let weatherConditions = ['rain', 'snow', 'sleet', 'hail', 'clear'];
 
 let todaysWeather = weatherConditions.slice(1, 3);

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/create-complex-multi-dimensional-arrays.english.md

@@ -9,7 +9,7 @@ challengeType: 1
 Awesome! You have just learned a ton about arrays! This has been a fairly high level overview, and there is plenty more to learn about working with arrays, much of which you will see in later sections. But before moving on to looking at <dfn>Objects</dfn>, lets take one more look, and see how arrays can become a bit more complex than what we have seen in previous challenges.
 One of the most powerful features when thinking of arrays as data structures, is that arrays can contain, or even be completely made up of other arrays. We have seen arrays that contain arrays in previous challenges, but fairly simple ones. However, arrays can contain an infinite depth of arrays that can contain other arrays, each with their own arbitrary levels of depth, and so on. In this way, an array can very quickly become very complex data structure, known as a <dfn>multi-dimensional</dfn>, or nested array. Consider the following example:
 
-```
+```js
 let nestedArray = [ // top, or first level - the outer most array
   ['deep'], // an array within an array, 2 levels of depth
   [
@@ -31,14 +31,14 @@ let nestedArray = [ // top, or first level - the outer most array
 While this example may seem convoluted, this level of complexity is not unheard of, or even unusual, when dealing with large amounts of data.
 However, we can still very easily access the deepest levels of an array this complex with bracket notation:
 
-```
+```js
 console.log(nestedArray[2][1][0][0][0]);
 // logs: deepest-est?
 ```
 
 And now that we know where that piece of data is, we can reset it if we need to:
 
-```
+```js
 nestedArray[2][1][0][0][0] = 'deeper still';
 
 console.log(nestedArray[2][1][0][0][0]);

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/iterate-through-all-an-arrays-items-using-for-loops.english.md

@@ -9,7 +9,7 @@ challengeType: 1
 Sometimes when working with arrays, it is very handy to be able to iterate through each item to find one or more elements that we might need, or to manipulate an array based on which data items meet a certain set of criteria. JavaScript offers several built in methods that each iterate over arrays in slightly different ways to achieve different results (such as <code>every()</code>, <code>forEach()</code>, <code>map()</code>, etc.), however the technique which is most flexible and offers us the greatest amount of control is a simple <code>for</code> loop.
 Consider the following:
 
-```
+```js
 function greaterThanTen(arr) {
   let newArr = [];
   for (let i = 0; i < arr.length; i++) {

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/modify-an-object-nested-within-an-object.english.md

@@ -8,7 +8,7 @@ challengeType: 1
 <section id='description'>
 Now let's take a look at a slightly more complex object. Object properties can be nested to an arbitrary depth, and their values can be any type of data supported by JavaScript, including arrays and even other objects. Consider the following:
 
-```
+```js
 let nestedObject = {
   id: 28802695164,
   date: 'December 31, 2016',

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/remove-items-from-an-array-with-pop-and-shift.english.md

@@ -9,7 +9,7 @@ challengeType: 1
 Both <code>push()</code> and <code>unshift()</code> have corresponding methods that are nearly functional opposites: <code>pop()</code> and <code>shift()</code>. As you may have guessed by now, instead of adding, <code>pop()</code> <em>removes</em> an element from the end of an array, while <code>shift()</code> removes an element from the beginning. The key difference between <code>pop()</code> and <code>shift()</code> and their cousins <code>push()</code> and <code>unshift()</code>, is that neither method takes parameters, and each only allows an array to be modified by a single element at a time.
 Let's take a look:
 
-```
+```js
 let greetings = ['whats up?', 'hello', 'see ya!'];
 
 greetings.pop();
@@ -21,7 +21,7 @@ greetings.shift();
 
 We can also return the value of the removed element with either method like this:
 
-```
+```js
 let popped = greetings.pop();
 // returns 'hello'
 // greetings now equals []

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/remove-items-using-splice.english.md

@@ -9,7 +9,7 @@ challengeType: 1
 Ok, so we've learned how to remove elements from the beginning and end of arrays using <code>shift()</code> and <code>pop()</code>, but what if we want to remove an element from somewhere in the middle? Or remove more than one element at once? Well, that's where <code>splice()</code> comes in. <code>splice()</code> allows us to do just that: <strong>remove any number of consecutive elements</strong> from anywhere in an array.
 <code>splice()</code> can take up to 3 parameters, but for now, we'll focus on just the first 2. The first two parameters of <code>splice()</code> are integers which represent indexes, or positions, of the array that <code>splice()</code> is being called upon. And remember, arrays are <em>zero-indexed</em>, so to indicate the first element of an array, we would use <code>0</code>. <code>splice()</code>'s first parameter represents the index on the array from which to begin removing elements, while the second parameter indicates the number of elements to delete. For example:
 
-```
+```js
 let array = ['today', 'was', 'not', 'so', 'great'];
 
 array.splice(2, 2);
@@ -19,7 +19,7 @@ array.splice(2, 2);
 
 <code>splice()</code> not only modifies the array it's being called on, but it also returns a new array containing the value of the removed elements:
 
-```
+```js
 let array = ['I', 'am', 'feeling', 'really', 'happy'];
 
 let newArray = array.splice(3, 2);

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/use-an-array-to-store-a-collection-of-data.english.md

@@ -8,7 +8,7 @@ challengeType: 1
 <section id='description'>
 The below is an example of the simplest implementation of an array data structure. This is known as a <dfn>one-dimensional array</dfn>, meaning it only has one level, or that it does not have any other arrays nested within it. Notice it contains <dfn>booleans</dfn>, <dfn>strings</dfn>, and <dfn>numbers</dfn>, among other valid JavaScript data types:
 
-```
+```js
 let simpleArray = ['one', 2, 'three', true, false, undefined, null];
 console.log(simpleArray.length);
 // logs 7
@@ -17,7 +17,7 @@ console.log(simpleArray.length);
 All arrays have a length property, which as shown above, can be very easily accessed with the syntax <code>Array.length</code>.
 A more complex implementation of an array can be seen below. This is known as a <dfn>multi-dimensional array</dfn>, or an array that contains other arrays. Notice that this array also contains JavaScript <dfn>objects</dfn>, which we will examine very closely in our next section, but for now, all you need to know is that arrays are also capable of storing complex objects.
 
-```
+```js
 let complexArray = [
   [
     {

curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-data-structures/use-the-delete-keyword-to-remove-object-properties.english.md

@@ -10,7 +10,7 @@ Now you know what objects are and their basic features and advantages. In short,
 In earlier challenges, we have both added to and modified an object's key-value pairs. Here we will see how we can <em>remove</em> a key-value pair from an object.
 Let's revisit our <code>foods</code> object example one last time. If we wanted to remove the <code>apples</code> key, we can remove it by using the <code>delete</code> keyword like this:
 
-```
+```js
 delete foods.apples;
 ```