21 lines
564 B
Python
21 lines
564 B
Python
from typing import List, Optional
|
|
|
|
|
|
def longest(strings: List[str]) -> Optional[str]:
|
|
""" Out of list of strings, return the longest one. Return the first one in case of multiple
|
|
strings of the same length. Return None in case the input list is empty.
|
|
>>> longest([])
|
|
|
|
>>> longest(['a', 'b', 'c'])
|
|
'a'
|
|
>>> longest(['a', 'bb', 'ccc'])
|
|
'ccc'
|
|
"""
|
|
if not strings:
|
|
return None
|
|
|
|
longest_str = strings[0]
|
|
for s in strings[1:]:
|
|
if len(s) > len(longest_str):
|
|
longest_str = s
|
|
return longest_str |