557. Reverse Words in a String III

Given a string, you need to reverse the order of characters in each word within a sentence while still preserving whitespace and initial word order.Example 1:Input: "Let's take LeetCode contest"Output: "s'teL ekat edoCteeL tsetnoc"Note: In the string, each word is separated by single space and there will not be any extra space in the string.

解一：

class Solution(object):    def reverseWords(self, s):        """        :type s: str        :rtype: str        """        #s = s.split(" ")        #rst = ""        #for string in s:        #    rst += string[::-1]        #    rst += " "        #return rst.rstrip()        return " ".join(map(lambda x: x[::-1], s.split()))

解二：

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

解三：

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

这里用到了string.join()
join()用于返回通过指定字符连接序列中元素后生成的新字符串。
map(fun, *arg),第一个是函数，第二个是传入函数的参数。
map是并行计算传入的参数。
split(’ ‘) 切分