Flatten a list

Write a program that prints every given list flattened. For example, $[[[a]], b]$ flattened is $[a, b]$ , and $[[a, b], [c, d]]$ flattened is $[a, b, c, d]$ .

Define and use a recursive function

flatten(t)

that flattens a list $t$ .

Hint

Using the @ast@ package, you can extract the list $t$ encoded in a string $s$ with @t = ast.literal_eval(s)@.

Input

The input consists of several lists.

Output

Print every given list flattened.

Problem information

Author: Gabriel Valiente

Generation: 2026-01-25T17:16:35.768Z