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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								id: 56105e7b514f539506016a5e
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								title: Count Backwards With a For Loop
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								challengeType: 1
							 
						 
					
						
							
								
									
										
										
										
											2019-02-14 12:24:02 -05:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								videoUrl: 'https://scrimba.com/c/c2R6BHa'
							 
						 
					
						
							
								
									
										
										
										
											2019-07-31 11:32:23 -07:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								forumTopicId: 16808
							 
						 
					
						
							
								
									
										
										
										
											2021-01-13 03:31:00 +01:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								dashedName: count-backwards-with-a-for-loop
							 
						 
					
						
							
								
									
										
										
										
											2018-09-30 23:01:58 +01:00 
										
									 
								 
							 
							
								
							 
							
								 
							
							
								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --description--
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								A for loop can also count backwards, so long as we can define the right conditions.
							 
						 
					
						
							
								
									
										
										
										
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								In order to decrement by two each iteration, we'll need to change our initialization, condition, and final expression.
							 
						 
					
						
							
								
									
										
										
										
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								We'll start at `i = 10`  and loop while `i > 0` . We'll decrement `i`  by 2 each loop with `i -= 2` .
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var ourArray = [];
							 
						 
					
						
							
								
									
										
										
										
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								for (var i = 10; i > 0; i -= 2) {
							 
						 
					
						
							
								
									
										
										
										
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								  ourArray.push(i);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
											2021-03-25 17:18:51 -05:00 
										
									 
								 
							 
							
								
									
										 
								
							 
							
								 
							
							
								`ourArray`  will now contain `[10,8,6,4,2]` . Let's change our initialization and final expression so we can count backwards by twos to create an array of descending odd numbers. 
						 
					
						
							
								
									
										
										
										
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								# --instructions--
  
						 
					
						
							
								
									
										
										
										
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								Push the odd numbers from 9 through 1 to `myArray`  using a `for`  loop.
							 
						 
					
						
							
								
									
										
										
										
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								# --hints--
  
						 
					
						
							
								
									
										
										
										
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								You should be using a `for`  loop for this.
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								assert(/for\s*\([^)]+?\)/.test(code));
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								You should be using the array method `push` .
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								assert(code.match(/myArray.push/));
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								`myArray`  should equal `[9,7,5,3,1]` . 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								assert.deepEqual(myArray, [9, 7, 5, 3, 1]);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --seed--
  
						 
					
						
							
								
									
										
										
										
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								## --after-user-code--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								if(typeof myArray !== "undefined"){(function(){return myArray;})();}
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								## --seed-contents--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								// Setup
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var myArray = [];
							 
						 
					
						
							
								
									
										
										
										
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								// Only change code below this line
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								# --solutions--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								var myArray = [];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								for (var i = 9; i > 0; i -= 2) {
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								  myArray.push(i);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								}
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```