# 535. Encode and Decode TinyURL

### Description

> Note: This is a companion problem to the [System Design](https://leetcode.com/discuss/interview-question/system-design/) problem: [Design TinyURL](https://leetcode.com/discuss/interview-question/124658/Design-a-URL-Shortener-\(-TinyURL-\)-System/).

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.

### Constraints

### Approach

### Links

* GeeksforGeeks
* [Leetcode](https://leetcode.com/problems/encode-and-decode-tinyurl/)
* ProgramCreek
* YouTube

### **Examples**

{% tabs %}
{% tab title="Example 1" %}

{% endtab %}
{% endtabs %}

### **Solutions**

{% tabs %}
{% tab title="Solution 1" %}

```java
/**
 * Time complexity : 
 * Space complexity : 
 */

public class Codec {
    
    private Map<String, String> longShortMap = new HashMap();
    private Map<String, String> shortLongMap = new HashMap();
    private final String TINY_URL = "http://tinyurl.com/";
    private int id = 0;
    private String code = "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";

    // Encodes a URL to a shortened URL.
    public String encode(String longUrl) {
        if(longShortMap.containsKey(longUrl)) {
            return longShortMap.get(longUrl);
        }
        StringBuilder shortUrl = new StringBuilder();
        int currId = id;
        for(int i = 0; i < 6; i++) {
            int codeIndex = currId % 62;
            currId /= 62;
            shortUrl.append(code.charAt(codeIndex));
        }
        longShortMap.put(longUrl, shortUrl.toString());
        shortLongMap.put(shortUrl.toString(), longUrl);
        id++;
        return TINY_URL + shortUrl.toString();
    }

    // Decodes a shortened URL to its original URL.
    public String decode(String shortUrl) {
        return shortLongMap.get(shortUrl.replace(TINY_URL, ""));
    }
}

// Your Codec object will be instantiated and called as such:
// Codec codec = new Codec();
// codec.decode(codec.encode(url));
```

{% endtab %}
{% endtabs %}

### **Follow up**

*


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://code-snippets.hbamithkumara.com/leetcode/problems/501-600/encode-and-decode-tinyurl.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.