reverse-words-in-a-string.py

# Time:  O(n)
# Space: O(n)
#
# Given an input string, reverse the string word by word.
# 
# For example,
# Given s = "the sky is blue",
# return "blue is sky the".
# 
# click to show clarification.
# 
# Clarification:
# What constitutes a word?
# A sequence of non-space characters constitutes a word.
# Could the input string contain leading or trailing spaces?
# Yes. However, your reversed string should not contain leading or trailing spaces.
# How about multiple spaces between two words?
# Reduce them to a single space in the reversed string.
#

class Solution:
    # @param s, a string
    # @return a string
    def reverseWords(self, s):
        return ' '.join(reversed(s.split()))

if __name__ == '__main__':
    print Solution().reverseWords('hello world')