runtime complexity of append python code example

Example 1: python append vs extend

my_list = [23, 11, 42, 24523]

# append will add it as if you're adding a new list to it
my_list.append([34523, 76979])
print(my_list)

# extend will go over each item in the new source list and add each
# element as part of the target list (my_list)
my_list.extend([12, 99])
print(my_list)

""" 
Output:
[23, 11, 42, 24523, [34523, 76979]]
[23, 11, 42, 24523, [34523, 76979], 12, 99]
"""

Example 2: python add all values of another list

a = [1, 2, 3]
b = [4, 5, 6]
a += b
# another way: a.extend(b)

Example 3: append a list to another list as element

a = ['Jon', 'janni', 'Jannardhan']
b = ['28', '29', '30']
a.append(b)
print(a)
a.pop()
a.extend(b)
print(a)