76 lines
2.5 KiB
Markdown
76 lines
2.5 KiB
Markdown
---
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id: 587d7db9367417b2b2512ba5
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title: Specify Upper and Lower Number of Matches
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challengeType: 1
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forumTopicId: 301367
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---
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## Description
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<section id='description'>
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Recall that you use the plus sign <code>+</code> to look for one or more characters and the asterisk <code>*</code> to look for zero or more characters. These are convenient but sometimes you want to match a certain range of patterns.
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You can specify the lower and upper number of patterns with <code>quantity specifiers</code>. Quantity specifiers are used with curly brackets (<code>{</code> and <code>}</code>). You put two numbers between the curly brackets - for the lower and upper number of patterns.
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For example, to match only the letter <code>a</code> appearing between <code>3</code> and <code>5</code> times in the string <code>"ah"</code>, your regex would be <code>/a{3,5}h/</code>.
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```js
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let A4 = "aaaah";
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let A2 = "aah";
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let multipleA = /a{3,5}h/;
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multipleA.test(A4); // Returns true
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multipleA.test(A2); // Returns false
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```
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</section>
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## Instructions
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<section id='instructions'>
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Change the regex <code>ohRegex</code> to match the entire phrase <code>"Oh no"</code> only when it has <code>3</code> to <code>6</code> letter <code>h</code>'s.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: Your regex should use curly brackets.
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testString: assert(ohRegex.source.match(/{.*?}/).length > 0);
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- text: Your regex should not match <code>"Ohh no"</code>
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testString: assert(!ohRegex.test("Ohh no"));
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- text: Your regex should match <code>"Ohhh no"</code>
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testString: assert("Ohhh no".match(ohRegex)[0].length === 7);
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- text: Your regex should match <code>"Ohhhh no"</code>
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testString: assert("Ohhhh no".match(ohRegex)[0].length === 8);
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- text: Your regex should match <code>"Ohhhhh no"</code>
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testString: assert("Ohhhhh no".match(ohRegex)[0].length === 9);
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- text: Your regex should match <code>"Ohhhhhh no"</code>
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testString: assert("Ohhhhhh no".match(ohRegex)[0].length === 10);
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- text: Your regex should not match <code>"Ohhhhhhh no"</code>
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testString: assert(!ohRegex.test("Ohhhhhhh no"));
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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
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let ohStr = "Ohhh no";
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let ohRegex = /change/; // Change this line
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let result = ohRegex.test(ohStr);
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```
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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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let ohStr = "Ohhh no";
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let ohRegex = /Oh{3,6} no/; // Change this line
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let result = ohRegex.test(ohStr);
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```
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</section>
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