Add find snippets
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snippets/find.md
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snippets/find.md
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---
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title: find
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tags: list,beginner
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---
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Returns the value of the first element in the provided list that satisfies the provided testing function.
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Use list comprehension and `next()` to return the first element in `lst` for which `fn` returns `True`.
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```py
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def find(lst, fn):
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return next(x for x in lst if fn(x))
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```
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```py
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find([1, 2, 3, 4], lambda n: n % 2 == 1) # 1
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```
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17
snippets/find_index.md
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17
snippets/find_index.md
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---
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title: find_index
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tags: list,beginner
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---
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Returns the index of the first element in the provided list that satisfies the provided testing function.
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Use list comprehension, `enumerate()` and `next()` to return the index of the first element in `lst` for which `fn` returns `True`.
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```py
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def find_index(lst, fn):
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return next(i for i, x in enumerate(lst) if fn(x))
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```
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```py
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find_index([1, 2, 3, 4], lambda n: n % 2 == 1) # 0
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```
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17
snippets/find_last.md
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snippets/find_last.md
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---
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title: find_last
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tags: list,beginner
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---
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Returns the value of the last element in the provided list that satisfies the provided testing function.
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Use list comprehension and `next()` to return the last element in `lst` for which `fn` returns `True`.
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```py
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def find_last(lst, fn):
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return next(x for x in lst[::-1] if fn(x))
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```
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```py
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find_last([1, 2, 3, 4], lambda n: n % 2 == 1) # 3
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```
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17
snippets/find_last_index.md
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17
snippets/find_last_index.md
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---
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title: find_last_index
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tags: list,beginner
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---
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Returns the index of the last element in the provided list that satisfies the provided testing function.
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Use list comprehension, `enumerate()` and `next()` to return the index of the last element in `lst` for which `fn` returns `True`.
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```py
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def find_last_index(lst, fn):
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return len(lst) - 1 - next(i for i, x in enumerate(lst[::-1]) if fn(x))
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```
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```py
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find_last_index([1, 2, 3, 4], lambda n: n % 2 == 1) # 2
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```
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