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							|  |  |  | id: 587d7db8367417b2b2512ba2 | 
					
						
							|  |  |  | title: Restrict Possible Usernames | 
					
						
							|  |  |  | challengeType: 1 | 
					
						
							|  |  |  | --- | 
					
						
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							|  |  |  | ## Description
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							|  |  |  | <section id='description'> | 
					
						
							|  |  |  | Usernames are used everywhere on the internet. They are what give users a unique identity on their favorite sites. | 
					
						
							|  |  |  | You need to check all the usernames in a database. Here are some simple rules that users have to follow when creating their username. | 
					
						
							|  |  |  | 1) The only numbers in the username have to be at the end. There can be zero or more of them at the end. | 
					
						
							|  |  |  | 2) Username letters can be lowercase and uppercase. | 
					
						
							|  |  |  | 3) Usernames have to be at least two characters long. A two-letter username can only use alphabet letter characters. | 
					
						
							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Instructions
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							|  |  |  | <section id='instructions'> | 
					
						
							|  |  |  | Change the regex <code>userCheck</code> to fit the constraints listed above. | 
					
						
							|  |  |  | </section> | 
					
						
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							|  |  |  | ## Tests
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							|  |  |  | <section id='tests'> | 
					
						
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							|  |  |  | ```yml | 
					
						
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										 |  |  | tests: | 
					
						
							|  |  |  |   - text: Your regex should match <code>JACK</code> | 
					
						
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										 |  |  |     testString: assert(userCheck.test("JACK"), 'Your regex should match <code>JACK</code>'); | 
					
						
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										 |  |  |   - text: Your regex should not match <code>J</code> | 
					
						
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										 |  |  |     testString: assert(!userCheck.test("J"), 'Your regex should not match <code>J</code>'); | 
					
						
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										 |  |  |   - text: Your regex should match <code>Oceans11</code> | 
					
						
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										 |  |  |     testString: assert(userCheck.test("Oceans11"), 'Your regex should match <code>Oceans11</code>'); | 
					
						
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										 |  |  |   - text: Your regex should match <code>RegexGuru</code> | 
					
						
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										 |  |  |     testString: assert(userCheck.test("RegexGuru"), 'Your regex should match <code>RegexGuru</code>'); | 
					
						
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										 |  |  |   - text: Your regex should not match <code>007</code> | 
					
						
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										 |  |  |     testString: assert(!userCheck.test("007"), 'Your regex should not match <code>007</code>'); | 
					
						
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										 |  |  |   - text: Your regex should not match <code>9</code> | 
					
						
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										 |  |  |     testString: assert(!userCheck.test("9"), 'Your regex should not match <code>9</code>'); | 
					
						
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										 |  |  |   - text: Your regex should not match <code>A1</code> | 
					
						
							|  |  |  |     testString: assert(!userCheck.test("A1"), 'Your regex should not match <code>A1</code>'); | 
					
						
							|  |  |  |   - text: Your regex should not match <code>BadUs3rnam3</code> | 
					
						
							|  |  |  |     testString: assert(!userCheck.test("BadUs3rnam3"), 'Your regex should not match <code>BadUs3rnam3</code>'); | 
					
						
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							|  |  |  | ``` | 
					
						
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							|  |  |  | </section> | 
					
						
							|  |  |  | 
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							|  |  |  | ## Challenge Seed
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							|  |  |  | <section id='challengeSeed'> | 
					
						
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							|  |  |  | <div id='js-seed'> | 
					
						
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							|  |  |  | ```js | 
					
						
							|  |  |  | let username = "JackOfAllTrades"; | 
					
						
							|  |  |  | let userCheck = /change/; // Change this line | 
					
						
							|  |  |  | let result = userCheck.test(username); | 
					
						
							|  |  |  | ``` | 
					
						
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							|  |  |  | </div> | 
					
						
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							|  |  |  | </section> | 
					
						
							|  |  |  | 
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							|  |  |  | ## Solution
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							|  |  |  | <section id='solution'> | 
					
						
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							|  |  |  | ```js | 
					
						
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										 |  |  | const userCheck = /^[A-Za-z]{2,}\d*$/; | 
					
						
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										 |  |  | ``` | 
					
						
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										 |  |  | </section> |