[LeetCode]535. Encode and Decode TinyURL

题目

TinyURL is a URL shortening service where you enter a URL such as https://leetcode.com/problems/design-tinyurl and it returns a short URL such as http://tinyurl.com/4e9iAk.

Design the encode and decode methods for the TinyURL service. There is no restriction on how your encode/decode algorithm should work. You just need to ensure that a URL can be encoded to a tiny URL and the tiny URL can be decoded to the original URL.

方法

提供一个map和变量i，每来一个url的时候i++，将url和i的对应关系存入map即可

python代码

class Codec:
    def __init__(self):
        self.map = {}
        self.i = 0
    
    def encode(self, longUrl):
        """Encodes a URL to a shortened URL.
        :type longUrl: str
        :rtype: str
        """
        self.i += 1
        self.map[self.i] = longUrl
        return "http://tinyurl.com/" + str(self.i)

    def decode(self, shortUrl):
        """Decodes a shortened URL to its original URL.
        :type shortUrl: str
        :rtype: str
        """
        return self.map[int(shortUrl.split('/')[-1])]

# Your Codes object will be instantiated and called as such:
# codec = Codec()
# codec.decode(codec.encode(url))

url = "https://leetcode.com/problems/design-tinyurl";
codec = Codec()
assert codec.decode(codec.encode(url)) == url