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.
public class Codec { Map<String, String> map = new HashMap<>(); String charSet = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; // Encodes a URL to a shortened URL. public String encode(String longUrl) { Random rand = new Random(); StringBuilder sb = new StringBuilder(); for (int i = 0; i < 6; i++) { int index = rand.nextInt(charSet.length()); sb.append(charSet.charAt(index)); } String url = "http://tinyurl.com/" + sb.toString(); if (!map.containsKey(url)) { map.put(url, longUrl); } return url; } // Decodes a shortened URL to its original URL. public String decode(String shortUrl) { return map.get(shortUrl); } } // Your Codec object will be instantiated and called as such: // Codec codec = new Codec(); // codec.decode(codec.encode(url));
[LC] 535. Encode and Decode TinyURL
原文：https://www.cnblogs.com/xuanlu/p/12785612.html