不要创建一个
list，请创建一个
set。它会在固定时间内进行查找。
如果您不希望集合的内存开销，则保留一个排序列表，然后使用
bisect模块进行搜索。
from bisect import bisect_leftdef bi_contains(lst, item): """ efficient `item in lst` for sorted lists """ # if item is larger than the last its not in the list, but the bisect would # find `len(lst)` as the index to insert, so check that first. Else, if the # item is in the list then it has to be at index bisect_left(lst, item) return (item <= lst[-1]) and (lst[bisect_left(lst, item)] == item)
