leetcode：535. TinyURL 的加密与解密【url和id的映射，id自增】

分析

简单url和id的映射

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最后一个
        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))

总结

url id 映射