Python 设置转换的列表的时间复杂度是多少？
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What is time complexity of a list to set conversion?
提问by lxuechen
I've noticed the table of the time complexity of set operations on the python official website. But i just wanna ask what's the time complexity of converting a list to a set, for instance,
我注意到python官网上的set操作的时间复杂度表。但我只想问问将列表转换为集合的时间复杂度是多少，例如，
l = [1, 2, 3, 4, 5]
s = set(l)
I kind of know that this is actually a hash table, but how exactly does it work? Is it O(n) then?
我知道这实际上是一个哈希表，但它究竟是如何工作的？那么是 O(n) 吗？
采纳答案by Mad Physicist
Yes. Iterating over a list is O(n)and adding each element to the hash set is O(1), so the total operation is O(n).
是的。遍历列表 isO(n)并将每个元素添加到哈希集 is O(1)，因此总操作是O(n)。
