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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								id: 56bbb991ad1ed5201cd392cc
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								title: Manipulate Arrays With pop()
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								challengeType: 1
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								## Description
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< section  id = 'description' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								Another way to change the data in an array is with the < code > .pop()< / code >  function.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< code > .pop()< / code >  is used to "pop" a value off of the end of an array. We can store this "popped off" value by assigning it to a variable. In other words, < code > .pop()< / code >  removes the last element from an array and returns that element. 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								Any type of entry can be "popped" off of an array - numbers, strings, even nested arrays.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< blockquote > < code > var threeArr = [1, 4, 6];< br >  var oneDown = threeArr.pop();< br >  console.log(oneDown); // Returns 6< br >  console.log(threeArr); // Returns [1, 4]< / code > < / blockquote >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
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								## Instructions
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< section  id = 'instructions' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								Use the < code > .pop()< / code >  function to remove the last item from < code > myArray< / code > , assigning the "popped off" value to < code > removedFromMyArray< / code > .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
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								## Tests
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< section  id = 'tests' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```yml
							 
						 
					
						
							
								
									
										
										
										
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								tests:
							 
						 
					
						
							
								
									
										
										
										
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								  -  text: < code > myArray</ code >  should only contain < code > [["John", 23]]</ code > .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								    testString: assert((function(d){if(d[0][0] == 'John' & &  d[0][1] === 23 & &  d[1] == undefined){return true;}else{return false;}})(myArray), '< code > myArray< / code >  should only contain < code > [["John", 23]]< / code > .');
							 
						 
					
						
							
								
									
										
										
										
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								  -  text: Use < code > pop()</ code >  on < code > myArray</ code > 
							 
						 
					
						
							
								
									
										
										
										
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								    testString: assert(/removedFromMyArray\s*=\s*myArray\s*.\s*pop\s*(\s*)/.test(code), 'Use < code > pop()</ code >  on < code > myArray</ code > ');
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  -  text: < code > removedFromMyArray</ code >  should only contain < code > ["cat", 2]</ code > .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								    testString: assert((function(d){if(d[0] == 'cat' & &  d[1] === 2 & &  d[2] == undefined){return true;}else{return false;}})(removedFromMyArray), '< code > removedFromMyArray< / code >  should only contain < code > ["cat", 2]< / code > .');
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / section >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								## Challenge Seed
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< section  id = 'challengeSeed' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< div  id = 'js-seed' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// Example
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var ourArray = [1,2,3];
							 
						 
					
						
							
								
									
										
										
										
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								var removedFromOurArray = ourArray.pop();
							 
						 
					
						
							
								
									
										
										
										
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								// removedFromOurArray now equals 3, and ourArray now equals [1,2]
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// Setup
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var myArray = [["John", 23], ["cat", 2]];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// Only change code below this line.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var removedFromMyArray;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / div >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								### After Test
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< div  id = 'js-teardown' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
									
										
										
										
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								(function(y, z){return 'myArray = ' + JSON.stringify(y) + ' &  removedFromMyArray = ' + JSON.stringify(z);})(myArray, removedFromMyArray);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / div >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / section >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								## Solution
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< section  id = 'solution' >  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var myArray = [["John", 23], ["cat", 2]];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var removedFromMyArray = myArray.pop();
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								< / section >