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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								id: 56bbb991ad1ed5201cd392ce
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								title: Manipulate Arrays With unshift()
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								challengeType: 1
							 
						 
					
						
							
								
									
										
										
										
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								videoUrl: 'https://scrimba.com/c/ckNDESv'
							 
						 
					
						
							
								
									
										
										
										
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								forumTopicId: 18239
							 
						 
					
						
							
								
									
										
										
										
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								dashedName: manipulate-arrays-with-unshift
							 
						 
					
						
							
								
									
										
										
										
											2018-09-30 23:01:58 +01:00 
										
									 
								 
							 
							
								
							 
							
								 
							
							
								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --description--
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								Not only can you `shift`  elements off of the beginning of an array, you can also `unshift`  elements to the beginning of an array i.e. add elements in front of the array.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								`.unshift()`  works exactly like `.push()` , but instead of adding the element at the end of the array, `unshift()`  adds the element at the beginning of the array. 
						 
					
						
							
								
									
										
										
										
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								Example:
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var ourArray = ["Stimpson", "J", "cat"];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								ourArray.shift(); // ourArray now equals ["J", "cat"]
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								ourArray.unshift("Happy");
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// ourArray now equals ["Happy", "J", "cat"]
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --instructions--
  
						 
					
						
							
								
									
										
										
										
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								Add `["Paul",35]`  to the beginning of the `myArray`  variable using `unshift()` .
							 
						 
					
						
							
								
									
										
										
										
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								# --hints--
  
						 
					
						
							
								
									
										
										
										
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								`myArray`  should now have `[["Paul", 35], ["dog", 3]]` . 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								assert(
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  (function (d) {
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								    if (
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      typeof d[0] === 'object' & & 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      d[0][0] == 'Paul' & & 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      d[0][1] === 35 & & 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      d[1][0] != undefined & & 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      d[1][0] == 'dog' & & 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      d[1][1] != undefined & & 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      d[1][1] == 3
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								    ) {
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      return true;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								    } else {
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								      return false;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								    }
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  })(myArray)
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --seed--
  
						 
					
						
							
								
									
										
										
										
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								## --after-user-code--
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								(function(y, z){return 'myArray = ' + JSON.stringify(y);})(myArray);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								## --seed-contents--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// Setup
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var myArray = [["John", 23], ["dog", 3]];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								myArray.shift();
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								// Only change code below this line
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --solutions--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var myArray = [["John", 23], ["dog", 3]];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								myArray.shift();
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								myArray.unshift(["Paul", 35]);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```