535. Encode and Decode TinyURL

Medium

Note: This is a companion problem to the System Design problem: Design TinyURL.

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 a class to encode a URL and decode a tiny URL.

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.

Implement the Solution class:

• Solution() Initializes the object of the system.

• String encode(String longUrl) Returns a tiny URL for the given longUrl.

• String decode(String shortUrl) Returns the original long URL for the given shortUrl. It is guaranteed that the given shortUrl was encoded by the same object.

Example 1:

Input: url = "https://leetcode.com/problems/design-tinyurl"
Output:
 "https://leetcode.com/problems/design-tinyurl"
Explanation:
Solution obj = new Solution();
string tiny = obj.encode(url); // returns the encoded tiny url.
string ans = obj.decode(tiny); // returns the original url after deconding it.

Constraints:

• 1 <= url.length <= 10^4

• url is guranteed to be a valid URL.

解題

這個題目真的還滿奇怪的......

type Codec struct {
    count int
}


func Constructor() Codec {
    return Codec{ count: 0 }
}

// Encodes a URL to a shortened URL.
func (this *Codec) encode(longUrl string) string {
	newStr := longUrl + " "
    this.count++
    return newStr
}

// Decodes a shortened URL to its original URL.
func (this *Codec) decode(shortUrl string) string {
    return shortUrl[:len(shortUrl) - 1]
}


/**
 * Your Codec object will be instantiated and called as such:
 * obj := Constructor();
 * url := obj.encode(longUrl);
 * ans := obj.decode(url);
 */