leetcode:Reverse Words in a String【Python版】

class Solution:
    # @param s, a string
    # @return a string
    def reverseWords(self, s):
        ss = s.split(" ")
        ss = filter(lambda x:x!="",ss)
        l = len(ss)
        for i in range(l/2):
            ss[i],ss[l-1-i] = ss[l-1-i],ss[i]
        s = (" ").join(ss)
        return s

为了去掉''字符，尝试了好几种方法，最后还是用filter函数将其过滤掉了。