T
кинь код текстом
from timeit import timeit
from itertools import chain
def insert_separator(old, sep):
items_count = len(old)
separators = (sep for _ in range(items_count))
result = []
for i, s in zip(old, separators):
result.append(i)
result.append(s)
return result[:-1]
def foo(lst, sep):
res = []
for i in lst:
res += [i, sep]
return res[:-1]
source = [1, 2, 3]
sep = None
N = len(source)
first = lambda: list(sum(zip(source, [sep]*N), tuple()))[:-1]
second = lambda: sum([[x, None] for x in source], list())[:-1]
third = lambda: list(chain(*([x, None] for x in source)))[:-1]
fourth = lambda: insert_separator(source, sep)
fifth = lambda: foo(source, sep)
print(timeit(first, number=10_000_000))
print(timeit(second, number=10_000_000))
print(timeit(third, number=10_000_000))
print(timeit(fourth, number=10_000_000))
print(timeit(fifth, number=10_000_000))
print(first())
print(second())
print(third())
print(fourth())
print(fifth())