0151. Reverse Words In A String

Medium

Given an input string s, reverse the order of the words.

A word is defined as a sequence of non-space characters. The words in s will be separated by at least one space.

Return a string of the words in reverse order concatenated by a single space.

Note that s may contain leading or trailing spaces or multiple spaces between two words. The returned string should only have a single space separating the words. Do not include any extra spaces.

Example 1:

Input: s = "the sky is blue"
Output: "blue is sky the"

Example 2:

Input: s = "  hello world  "
Output: "world hello"
Explanation: Your reversed string should not contain leading or trailing spaces.

Example 3:

Input: s = "a good   example"
Output: "example good a"
Explanation: You need to reduce multiple spaces between two words to a single space in the reversed string.

Constraints:

1 <= s.length <= 10⁴
s contains English letters (upper-case and lower-case), digits, and spaces ' '.
There is at least one word in s.

Follow-up: If the string data type is mutable in your language, can you solve it in-place with O(1) extra space?

 class Solution:
    def reverseWords(self, s: str) -> str:

#         list_data = s.strip().split(" ")
#         list_data.reverse()
#         list_data = [s.strip() for s in list_data ]

#         list_data = list(filter(None, list_data))


#         #print(list_data)

#         return " ".join(list_data)

        return ' '.join(s.split()[::-1])

0151. Reverse Words In A String

Random Note