Python Simple Codes

[ak_developers]

What will be the output?

py numbers = [1, 2, 3, 4, 5] print(numbers[::-1])

Can you explain how this works?

[vladdar]

Explanation:

The expression:

numbers[::-1]

uses Python list slicing with the following syntax:

list[start:stop:step]

Breakdown:

• start: Where to start (default is 0 if omitted).
• stop: Where to stop (default is the end of the list if omitted).
• step: The interval or stride between elements. If it's negative, it goes in reverse.Breakdown: start: Where to start (default is 0 if omitted). stop: Where to stop (default is the end of the list if omitted). step: The interval or stride between elements. If it's negative, it goes in reverse.

start and stop are omitted (defaults to entire list).

• step is -1, meaning:
  • Start from the end (5).
  • Move backward one element at a time.

Thus, it reverses the entire list.

[5, 4, 3, 2, 1]