leetcode151.py

"""
Top 75 Interview Question, Reverse Words in a String, leetcode151

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.
"""

# Final Solution beats 81% runtime:
class Solution(object):
    def reverseWords(self, s):
        """
        :type s: str
        :rtype: str
        """
        words = s.split() # gets words split by blank
        answer = '' # final answer
        #print(words)
        for w in words:
            w = w +' ' # add a space after word
            answer = str(w) + answer # store answer with the w first
            #print(w)
        return answer[:-1] # remove the final space, not needed