83 lines
1.5 KiB
Markdown
83 lines
1.5 KiB
Markdown
---
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id: 587d7b7e367417b2b2512b22
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title: Use the parseInt Function with a Radix
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/c6K4Kh3'
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forumTopicId: 301182
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dashedName: use-the-parseint-function-with-a-radix
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---
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# --description--
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The `parseInt()` function parses a string and returns an integer. It takes a second argument for the radix, which specifies the base of the number in the string. The radix can be an integer between 2 and 36.
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The function call looks like:
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```js
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parseInt(string, radix);
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```
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And here's an example:
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```js
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var a = parseInt("11", 2);
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```
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The radix variable says that `11` is in the binary system, or base 2. This example converts the string `11` to an integer `3`.
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# --instructions--
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Use `parseInt()` in the `convertToInteger` function so it converts a binary number to an integer and returns it.
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# --hints--
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`convertToInteger` should use the `parseInt()` function
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```js
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assert(/parseInt/g.test(code));
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```
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`convertToInteger("10011")` should return a number
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```js
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assert(typeof convertToInteger('10011') === 'number');
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```
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`convertToInteger("10011")` should return 19
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```js
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assert(convertToInteger('10011') === 19);
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```
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`convertToInteger("111001")` should return 57
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```js
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assert(convertToInteger('111001') === 57);
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```
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`convertToInteger("JamesBond")` should return `NaN`
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```js
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assert.isNaN(convertToInteger('JamesBond'));
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```
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# --seed--
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## --seed-contents--
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```js
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function convertToInteger(str) {
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}
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convertToInteger("10011");
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```
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# --solutions--
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```js
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function convertToInteger(str) {
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return parseInt(str, 2);
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}
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```
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