"""

Reverse Words in a String

Given a string, reverse the order of words. Leading and trailing spaces

are trimmed and words are separated by single spaces.

Reference: https://leetcode.com/problems/reverse-words-in-a-string/

Complexity:

Time: O(n) where n is the length of the string

Space: O(n)

"""

from __future__ import annotations

def _reverse_list(array: list[str], left: int, right: int) -> None:

"""Reverse a portion of a list in place.

Args:

array: The list to modify.

left: The starting index.

right: The ending index.

"""

while left < right:

array[left], array[right] = array[right], array[left]

left += 1

right -= 1

def reverse_words(string: str) -> str:

"""Reverse the order of words in a string.

Args:

string: The input string of words.

Returns:

A string with the word order reversed.

Examples:

>>> reverse_words("I am keon kim and I like pizza")

'pizza like I and kim keon am I'

"""

words = string.strip().split()

word_count = len(words)

_reverse_list(words, 0, word_count - 1)

return " ".join(words)