Introduction
Sorting – sort()
Sorting – sorted()
Sorting – reverse() and reversed()
Instruction
Excellent! Next, there is a function named reverse() that – as the name suggests – reverses the order of elements in a list. Take a look:
books = [ 'Sound of Steel', 'Silent Duty', 'Marked for Crime', 'Faceless Tribunal', 'Enemy of Evil', 'Shot for Gold', 'Beyond the Storm' ] books.reverse()
Note that reverse() works in place – i.e., it modifies the original variable. After this invocation, the books list will have its elements in the following order:
[ 'Beyond the Storm', 'Shot for Gold', 'Enemy of Evil', 'Faceless Tribunal', 'Marked for Crime', 'Silent Duty', 'Sound of Steel' ]
Exercise
We define a list as symmetrical if reversing the list yields the same list, e.g.:
- Symmetrical:
[1, 2, 3, 2, 1] - Not symmetrical:
[1, 2, 3, 4]
Write a function named is_symmetrical(input_list) that returns True if input_list is symmetrical and False otherwise. Do not modify the original list.
Stuck? Here's a hint!
Because reverse() works in place, you'll need to create a copy of the list with list(input_list) and reverse the copy. Then, compare the two lists.
