9 lines
271 B
Markdown
9 lines
271 B
Markdown
### Array difference (complement)
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Create a `Set` from `b`, then use `Array.filter()` on `a` to only keep values not contained in `b`.
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```js
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const difference = (a, b) => { const s = new Set(b); return a.filter(x => !s.has(x)); }
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// difference([1,2,3], [1,2]) -> [3]
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```
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