append_vs_insert.py

import random
import time

N = 100000
lst1 = [random.randint(0, 9) for _ in range(N)]
lst2 = lst1.copy()


# insert
start1 = time.time()

lst = lst1
new_lst = []
while lst:
    e = lst.pop()
    if e % 2 == 0:
        new_lst.insert(0, e)

end1 = time.time()


# append, reverse
start2 = time.time()

lst = lst1
new_lst = []
while lst:
    e = lst.pop()
    if e % 2 == 0:
        new_lst.append(e)
else:
    new_lst.reverse()

end2 = time.time()


#
print('insert:', end1 - start1)
print('append, reverse:', end2 - start2)