Flattening List

[mp3909]

Just a curious question, how would one flatten the following list [[[2], [4, 1, 3]], [5, 7], 1, 10, [[[5, 5, 5], [4, 4, 4]]]] ?

[league55]

I think with zip().

[Gribouillis]

Here is a recursive solution

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from itertools import chain   def iflatten(seq):     return chain.from_iterable(         iflatten(x) if isinstance(x, list) else (x,) for x in seq)   def flatten(seq):     return list(iflatten(seq))   if __name__ == '__main__':     L = [[[2], [4, 1, 3]], [5, 7], 1, 10, [[[5, 5, 5], [4, 4, 4]]]]     print(flatten(L))

Output:
[2, 4, 1, 3, 5, 7, 1, 10, 5, 5, 5, 4, 4, 4]

[ka06059]

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def flatten(list):     flatted = []     for element in list:         if type(element) != type([]):             flatted+=[element]         else:             flatted+=flatten(element)     return flatted A = [[[2], [4, 1, 3]], [5, 7], 1, 10, [[[5, 5, 5], [4, 4, 4]]]] flatten(A)

codes with basic keywords and list operation only

[Mekire]

Black magic:

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>>> a = [[[2], [4, 1, 3]], [5, 7], 1, 10, [[[5, 5, 5], [4, 4, 4]]]] >>> b = eval(repr(a).replace("[","").replace("]","")) >>> b (2, 4, 1, 3, 5, 7, 1, 10, 5, 5, 5, 4, 4, 4) >>>

But, in all seriousness, don't do that.

eval is bad, you say? I know:

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>>> a = [[[2], [4, 1, 3]], [5, 7], 1, 10, [[[5, 5, 5], [4, 4, 4]]]] >>> b = list(map(int, repr(a).replace("[","").replace("]","").split(","))) >>> b [2, 4, 1, 3, 5, 7, 1, 10, 5, 5, 5, 4, 4, 4] >>>

Don't do this either.

[Gribouillis]

Black magic:

There will be some trouble if the list contains literal strings instead of integers!

[Mekire]

Black magic:

There will be some trouble if the list contains literal strings instead of integers!

The dark arts can be cruel and unforgiving.

[league55]

Teaching the Qliphoth is forbidden, my friends.

[snippsat]

I want to break Python 2 support bye using yield from.

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def flatten(seq):     for item in seq:         if isinstance(item, list):             yield from flatten(item)         else:             yield item   lst = [[[2], [4, 1, 3]], [5, 7], 1, 10, [[[5, 5, 5], [4, 4, 4]]]] print(list(flatten(lst)))

Output:
[2, 4, 1, 3, 5, 7, 1, 10, 5, 5, 5, 4, 4, 4]