32 lines
648 B
Markdown
32 lines
648 B
Markdown
---
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title: Hash string into number
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tags: math
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expertise: intermediate
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cover: blog_images/dark-leaves.jpg
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firstSeen: 2017-12-27T17:12:34+02:00
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lastUpdated: 2020-10-22T20:24:30+03:00
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---
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Hashes the input string into a whole number.
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- Use `String.prototype.split()` and `Array.prototype.reduce()` to create a hash of the input string, utilizing bit shifting.
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```js
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const sdbm = str => {
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let arr = str.split('');
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return arr.reduce(
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(hashCode, currentVal) =>
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(hashCode =
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currentVal.charCodeAt(0) +
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(hashCode << 6) +
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(hashCode << 16) -
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hashCode),
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0
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);
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};
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```
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```js
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sdbm('name'); // -3521204949
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```
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