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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								id: 587d7db5367417b2b2512b96
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								title: Match Letters of the Alphabet
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								challengeType: 1
							 
						 
					
						
							
								
									
										
										
										
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								forumTopicId: 301354
							 
						 
					
						
							
								
									
										
										
										
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								dashedName: match-letters-of-the-alphabet
							 
						 
					
						
							
								
									
										
										
										
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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --description--
  
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								You saw how you can use < dfn > character sets< / dfn >  to specify a group of characters to match, but that's a lot of typing when you need to match a large range of characters (for example, every letter in the alphabet). Fortunately, there is a built-in feature that makes this short and simple.
							 
						 
					
						
							
								
									
										
										
										
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								Inside a character set, you can define a range of characters to match using a hyphen character: `-` .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								For example, to match lowercase letters `a`  through `e`  you would use `[a-e]` .
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let catStr = "cat";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let batStr = "bat";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let matStr = "mat";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let bgRegex = /[a-e]at/;
							 
						 
					
						
							
								
									
										
										
										
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								catStr.match(bgRegex);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								batStr.match(bgRegex);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								matStr.match(bgRegex);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								In order, the three `match`  calls would return the values `["cat"]` , `["bat"]` , and `null` .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --instructions--
  
						 
					
						
							
								
									
										
										
										
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								Match all the letters in the string `quoteSample` .
							 
						 
					
						
							
								
									
										
										
										
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								**Note**: Be sure to match both uppercase and lowercase letters.
							 
						 
					
						
							
								
									
										
										
										
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								# --hints--
  
						 
					
						
							
								
									
										
										
										
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								Your regex `alphabetRegex`  should match 35 items.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								assert(result.length == 35);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								Your regex `alphabetRegex`  should use the global flag.
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								assert(alphabetRegex.flags.match(/g/).length == 1);
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								Your regex `alphabetRegex`  should use the case insensitive flag.
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								assert(alphabetRegex.flags.match(/i/).length == 1);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								# --seed--
  
						 
					
						
							
								
									
										
										
										
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								## --seed-contents--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let quoteSample = "The quick brown fox jumps over the lazy dog.";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let alphabetRegex = /change/; // Change this line
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let result = alphabetRegex; // Change this line
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								```
							 
						 
					
						
							
								
									
										
										
										
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								# --solutions--
  
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
									
										
										
										
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								let quoteSample = "The quick brown fox jumps over the lazy dog.";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let alphabetRegex = /[a-z]/gi; // Change this line
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							
							
								let result = quoteSample.match(alphabetRegex); // Change this line
							 
						 
					
						
							
								
									
										
										
										
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								```