How Can I Reverse a Python List and Iterate Through It Backwards?

Iterating Over Lists Backwards

Question: How can you access elements of a list in reverse order?

Answer: Python provides several options for traversing lists in reverse or obtaining their reversed versions.

Creating a Reversed Copy:

To create a new list with the elements in reverse order, use the reversed() function and convert the result to a list:

xs = [0, 10, 20, 40]
reversed_xs = list(reversed(xs))
print(reversed_xs)  # Output: [40, 20, 10, 0]

Iterating Backwards:

Iterate backwards through a list by using reversed() within a for loop:

xs = [0, 10, 20, 40]
for x in reversed(xs):
    print(x)  # Output: 40, 20, 10, 0

This approach uses lazy evaluation, meaning Python only reverses the elements as they are accessed, reducing memory overhead compared to creating a new reversed list.

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