124 lines
2.2 KiB
Markdown
124 lines
2.2 KiB
Markdown
---
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id: 587d7db8367417b2b2512ba2
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title: Restrict Possible Usernames
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challengeType: 1
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forumTopicId: 301363
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dashedName: restrict-possible-usernames
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---
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# --description--
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Usernames are used everywhere on the internet. They are what give users a unique identity on their favorite sites.
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You need to check all the usernames in a database. Here are some simple rules that users have to follow when creating their username.
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1) Usernames can only use alpha-numeric characters.
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2) The only numbers in the username have to be at the end. There can be zero or more of them at the end. Username cannot start with the number.
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3) Username letters can be lowercase and uppercase.
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4) Usernames have to be at least two characters long. A two-character username can only use alphabet letters as characters.
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# --instructions--
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Change the regex `userCheck` to fit the constraints listed above.
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# --hints--
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Your regex should match `JACK`
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```js
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assert(userCheck.test('JACK'));
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```
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Your regex should not match `J`
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```js
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assert(!userCheck.test('J'));
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```
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Your regex should match `Jo`
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```js
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assert(userCheck.test('Jo'));
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```
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Your regex should match `Oceans11`
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```js
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assert(userCheck.test('Oceans11'));
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```
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Your regex should match `RegexGuru`
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```js
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assert(userCheck.test('RegexGuru'));
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```
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Your regex should not match `007`
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```js
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assert(!userCheck.test('007'));
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```
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Your regex should not match `9`
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```js
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assert(!userCheck.test('9'));
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```
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Your regex should not match `A1`
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```js
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assert(!userCheck.test('A1'));
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```
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Your regex should not match `BadUs3rnam3`
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```js
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assert(!userCheck.test('BadUs3rnam3'));
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```
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Your regex should match `Z97`
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```js
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assert(userCheck.test('Z97'));
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```
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Your regex should not match `c57bT3`
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```js
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assert(!userCheck.test('c57bT3'));
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```
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Your regex should match `AB1`
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```js
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assert(userCheck.test('AB1'));
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```
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Your regex should not match `J%4`
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```js
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assert(!userCheck.test('J%4'))
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```
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# --seed--
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## --seed-contents--
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```js
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let username = "JackOfAllTrades";
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let userCheck = /change/; // Change this line
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let result = userCheck.test(username);
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```
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# --solutions--
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```js
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let username = "JackOfAllTrades";
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const userCheck = /^[a-z]([0-9]{2,}|[a-z]+\d*)$/i;
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let result = userCheck.test(username);
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```
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