To convert the provided HTML content to Markdown, you can use the following Markdown representation:
Array slicing involves taking a subset from an array and allocating a new array with those elements.
In Python 3.6 you can create a new list of the elements in my_list, from start_index to end_index (exclusive), like this:
python
my_list[start_index:end_index]You can also get everything from start_index onwards by just omitting end_index:
python
my_list[start_index:]Careful: there's a hidden time and space cost here! It's tempting to think of slicing as just "getting elements," but in reality you are:
- allocating a new list
- copying the elements from the original list to the new list
This takes
$$O(n)$$
time and
$$O(n)$$
space, where $$n$$ is the number of elements in the resulting list.
That's a bit easier to see when you save the result of the slice to a variable:
python
tail_of_list = my_list[1:]But a bit harder to see when you don't save the result of the slice to a variable:
python
return my_list[1:] # Whoops, I just spent O(n) time and space!For item in slice:
python
for item in my_list[1:]:
pass # Whoops, I just spent O(n) time and space!So keep an eye out. Slice wisely.
