leetcode刷题：（python）344.反转字符串& 541. 反转字符串II&剑指Offer 05.替换空格&151.翻转字符串里的单词& 剑指Offer58-II.左旋转字符串

344.反转字符串

python使用转换字符串或列表顺序so easy 

都能笑死

class Solution:
    def reverseString(self, s: List[str]) -> None:
        """
        Do not return anything, modify s in-place instead.
        """
        s.reverse()

541. 反转字符串II

class Solution:
    def reverseStr(self, s: str, k: int) -> str:
        p = 0
        while p < len(s):
            p2 = p + k
            s = s[:p] + s[p:p2][::-1] +s[p2:]#字符串下标不用考虑越界
            p = p + 2*k
        return s
             


        

由于字符串不用考虑上下界超出所以问题变得简答起来

且又学一样：

字符串在指定下标反转：

string[left:right][::-1]

05.替换空格

so easy

class Solution:
    def pathEncryption(self, path: str) -> str:
        return path.replace('.',' ')

151.翻转字符串里的单词

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

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

 剑指Offer58-II.左旋转字符串

class Solution:
    def dynamicPassword(self, password: str, target: int) -> str:
        return password[target:]+password[:target]