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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								id: 587d78b2367417b2b2512b10
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								title: Remove Items Using splice()
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								challengeType: 1
							 
						 
					
						
							
								
									
										
										
										
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								forumTopicId: 301166
							 
						 
					
						
							
								
									
										
										
										
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								dashedName: remove-items-using-splice
							 
						 
					
						
							
								
									
										
										
										
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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --description--
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								Ok, so we've learned how to remove elements from the beginning and end of arrays using `shift()`  and `pop()` , 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 `splice()`  comes in. `splice()`  allows us to do just that: **remove any number of consecutive elements**  from anywhere in an array.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								`splice()`  can take up to 3 parameters, but for now, we'll focus on just the first 2. The first two parameters of `splice()`  are integers which represent indexes, or positions, of the array that `splice()`  is being called upon. And remember, arrays are *zero-indexed* , so to indicate the first element of an array, we would use `0` . `splice()` '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:
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								let array = ['today', 'was', 'not', 'so', 'great'];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								array.splice(2, 2);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								Here we remove 2 elements, beginning with the third element (at index 2). `array`  would have the value `['today', 'was', 'great']` .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								`splice()`  not only modifies the array it's being called on, but it also returns a new array containing the value of the removed elements:
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								let array = ['I', 'am', 'feeling', 'really', 'happy'];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								let newArray = array.splice(3, 2);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								`newArray`  has the value `['really', 'happy']` .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --instructions--
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								We've initialized an array `arr` . Use `splice()`  to remove elements from `arr` , so that it only contains elements that sum to the value of `10` .
							 
						 
					
						
							
								
									
										
										
										
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								# --hints--
 
							 
						 
					
						
							
								
									
										
										
										
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								You should not change the original line of `const arr = [2, 4, 5, 1, 7, 5, 2, 1];` .
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								assert(
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  __helpers.removeWhiteSpace(code).match(/constarr=\[2,4,5,1,7,5,2,1\];?/)
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								`arr`  should only contain elements that sum to `10` .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								assert.strictEqual(
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  arr.reduce((a, b) => a + b),
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  10
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								Your code should utilize the `splice()`  method on `arr` .
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								assert(__helpers.removeWhiteSpace(code).match(/arr\.splice\(/));
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								The splice should only remove elements from `arr`  and not add any additional elements to `arr` .
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								assert(
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  !__helpers.removeWhiteSpace(code).match(/arr\.splice\(\d+,\d+,\d+.*\)/g)
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								# --seed--
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								## --seed-contents--
 
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								const arr = [2, 4, 5, 1, 7, 5, 2, 1];
							 
						 
					
						
							
								
									
										
										
										
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								// Only change code below this line
							 
						 
					
						
							
								
									
										
										
										
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								// Only change code above this line
							 
						 
					
						
							
								
									
										
										
										
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								console.log(arr);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --solutions--
 
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								const arr = [2, 4, 5, 1, 7, 5, 2, 1];
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								arr.splice(1, 4);
							 
						 
					
						
							
								
									
										
										
										
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								```