leetcode：535. Encryption and decryption of tinyurl [mapping of URL and ID, ID self increment]

analysis

Simple url and id Mapping

ac code

class Codec:

    def __init__(self):
        self.id = 0
        self.db = {
    }

    def encode(self, longUrl: str) -> str:
        """Encodes a URL to a shortened URL. """
        self.id += 1
        self.db[self.id] = longUrl
        return 'http://tinyurl.com/' + str(self.id)

        
        

    def decode(self, shortUrl: str) -> str:
        """Decodes a shortened URL to its original URL. """
        # rfind the last one 
        idx = shortUrl.rfind('/')
        id = int(shortUrl[idx + 1:])
        return self.db[id]

        
        

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

summary

url id mapping