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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								id: 587d7db5367417b2b2512b96
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								title: Match Letters of the Alphabet
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								challengeType: 1
							 
						 
					
						
							
								
									
										
										
										
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								forumTopicId: 301354
							 
						 
					
						
							
								
									
										
										
										
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								---
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								## Description
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< section  id = 'description' > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								You saw how you can use < code > character sets< / code >  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.
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								Inside a < code > character set< / code > , you can define a range of characters to match using a < code > hyphen< / code >  character: < code > -< / code > .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								For example, to match lowercase letters < code > a< / code >  through < code > e< / code >  you would use < code > [a-e]< / code > .
							 
						 
					
						
							
								
									
										
										
										
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								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								let catStr = "cat";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								let batStr = "bat";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								let matStr = "mat";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								let bgRegex = /[a-e]at/;
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								catStr.match(bgRegex); // Returns ["cat"]
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								batStr.match(bgRegex); // Returns ["bat"]
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								matStr.match(bgRegex); // Returns null
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
									
										
										
										
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								< / section > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								## Instructions
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< section  id = 'instructions' > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								Match all the letters in the string < code > quoteSample< / code > .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< strong > Note< / strong > < br > Be sure to match both upper- and lowercase < strong > letters< strong > .
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< / section > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								## Tests
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< section  id = 'tests' > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```yml
							 
						 
					
						
							
								
									
										
										
										
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								tests:
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								  -  text: Your regex < code > alphabetRegex</ code >  should match 35 items.
							 
						 
					
						
							
								
									
										
										
										
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								    testString: assert(result.length == 35);
							 
						 
					
						
							
								
									
										
										
										
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								  -  text: Your regex < code > alphabetRegex</ code >  should use the global flag.
							 
						 
					
						
							
								
									
										
										
										
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								    testString: assert(alphabetRegex.flags.match(/g/).length == 1);
							 
						 
					
						
							
								
									
										
										
										
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								  -  text: Your regex < code > alphabetRegex</ code >  should use the case insensitive flag.
							 
						 
					
						
							
								
									
										
										
										
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								    testString: assert(alphabetRegex.flags.match(/i/).length == 1);
							 
						 
					
						
							
								
									
										
										
										
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								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< / section > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								## Challenge Seed
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< section  id = 'challengeSeed' > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< div  id = 'js-seed' > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```js
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								let quoteSample = "The quick brown fox jumps over the lazy dog.";
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								let alphabetRegex = /change/; // Change this line
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								let result = alphabetRegex; // Change this line
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< / div > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< / section > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								## Solution
 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								< section  id = 'solution' > 
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								
							 
						 
					
						
							
								
							 
							
								
							 
							
								 
							 
							
							
								```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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								```
							 
						 
					
						
							
								
									
										
										
										
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								< / section >