111 lines
3.0 KiB
Markdown
111 lines
3.0 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244dd
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title: Selecting from Many Options with Switch Statements
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c4mv4fm'
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---
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## Description
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<section id='description'>
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If you have many options to choose from, use a <code>switch</code> statement. A <code>switch</code> statement tests a value and can have many <code>case</code> statements which define various possible values. Statements are executed from the first matched <code>case</code> value until a <code>break</code> is encountered.
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Here is a <dfn>pseudocode</dfn> example:
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```js
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switch(num) {
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case value1:
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statement1;
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break;
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case value2:
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statement2;
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break;
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...
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case valueN:
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statementN;
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break;
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}
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```
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<code>case</code> values are tested with strict equality (<code>===</code>). The <code>break</code> tells JavaScript to stop executing statements. If the <code>break</code> is omitted, the next statement will be executed.
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</section>
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## Instructions
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<section id='instructions'>
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Write a switch statement which tests <code>val</code> and sets <code>answer</code> for the following conditions:<br><code>1</code> - "alpha"<br><code>2</code> - "beta"<br><code>3</code> - "gamma"<br><code>4</code> - "delta"
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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: <code>caseInSwitch(1)</code> should have a value of "alpha"
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testString: assert(caseInSwitch(1) === "alpha", '<code>caseInSwitch(1)</code> should have a value of "alpha"');
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- text: <code>caseInSwitch(2)</code> should have a value of "beta"
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testString: assert(caseInSwitch(2) === "beta", '<code>caseInSwitch(2)</code> should have a value of "beta"');
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- text: <code>caseInSwitch(3)</code> should have a value of "gamma"
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testString: assert(caseInSwitch(3) === "gamma", '<code>caseInSwitch(3)</code> should have a value of "gamma"');
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- text: <code>caseInSwitch(4)</code> should have a value of "delta"
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testString: assert(caseInSwitch(4) === "delta", '<code>caseInSwitch(4)</code> should have a value of "delta"');
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- text: You should not use any <code>if</code> or <code>else</code> statements
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testString: assert(!/else/g.test(code) || !/if/g.test(code), 'You should not use any <code>if</code> or <code>else</code> statements');
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- text: You should have at least 3 <code>break</code> statements
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testString: assert(code.match(/break/g).length > 2, 'You should have at least 3 <code>break</code> statements');
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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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function caseInSwitch(val) {
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var answer = "";
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// Only change code below this line
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// Only change code above this line
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return answer;
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}
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// Change this value to test
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caseInSwitch(1);
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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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function caseInSwitch(val) {
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var answer = "";
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switch(val) {
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case 1:
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answer = "alpha";
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break;
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case 2:
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answer = "beta";
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break;
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case 3:
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answer = "gamma";
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break;
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case 4:
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answer = "delta";
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}
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return answer;
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}
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```
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</section>
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