24 lines
490 B
Markdown
24 lines
490 B
Markdown
---
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title: List intersection
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type: snippet
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language: python
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tags: [list]
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cover: wooden-bowl
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dateModified: 2020-11-02T19:28:05+02:00
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---
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Returns a list of elements that exist in both lists.
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- Create a `set` from `a` and `b`.
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- Use the built-in set operator `&` to only keep values contained in both sets, then transform the `set` back into a `list`.
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```py
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def intersection(a, b):
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_a, _b = set(a), set(b)
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return list(_a & _b)
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```
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```py
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intersection([1, 2, 3], [4, 3, 2]) # [2, 3]
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```
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