Add solution 535

leetcode/0535.Encode-and-Decode-TinyURL/535. Encode and Decode TinyURL.go

@@ -0,0 +1,35 @@
+package leetcode
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+type Codec struct {
+	urls []string
+}
+
+func Constructor() Codec {
+	return Codec{[]string{}}
+}
+
+// Encodes a URL to a shortened URL.
+func (this *Codec) encode(longUrl string) string {
+	this.urls = append(this.urls, longUrl)
+	return "http://tinyurl.com/" + fmt.Sprintf("%v", len(this.urls)-1)
+}
+
+// Decodes a shortened URL to its original URL.
+func (this *Codec) decode(shortUrl string) string {
+	tmp := strings.Split(shortUrl, "/")
+	i, _ := strconv.Atoi(tmp[len(tmp)-1])
+	return this.urls[i]
+}
+
+/**
+ * Your Codec object will be instantiated and called as such:
+ * obj := Constructor();
+ * url := obj.encode(longUrl);
+ * ans := obj.decode(url);
+ */

leetcode/0535.Encode-and-Decode-TinyURL/535. Encode and Decode TinyURL_test.go

@@ -0,0 +1,15 @@
+package leetcode
+
+import (
+	"fmt"
+	"testing"
+)
+
+func Test_Problem535(t *testing.T) {
+	obj := Constructor()
+	fmt.Printf("obj = %v\n", obj)
+	e := obj.encode("https://leetcode.com/problems/design-tinyurl")
+	fmt.Printf("obj encode = %v\n", e)
+	d := obj.decode(e)
+	fmt.Printf("obj decode = %v\n", d)
+}

leetcode/0535.Encode-and-Decode-TinyURL/README.md

@@ -0,0 +1,60 @@
+# [535. Encode and Decode TinyURL](https://leetcode.com/problems/encode-and-decode-tinyurl/)
+
+
+## 题目
+
+> 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 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.
+
+## 题目大意
+
+TinyURL是一种URL简化服务， 比如：当你输入一个URL [https://leetcode.com/problems/design-tinyurl](https://leetcode.com/problems/design-tinyurl) 时，它将返回一个简化的URL [http://tinyurl.com/4e9iAk](http://tinyurl.com/4e9iAk).
+
+要求：设计一个 TinyURL 的加密 encode 和解密 decode 的方法。你的加密和解密算法如何设计和运作是没有限制的，你只需要保证一个URL可以被加密成一个TinyURL，并且这个TinyURL可以用解密方法恢复成原本的URL。
+
+## 解题思路
+
+- 简单题。由于题目并无规定 `encode()` 算法，所以自由度非常高。最简单的做法是把原始 `URL` 存起来，并记录下存在字符串数组中的下标位置。`decode()` 的时候根据存储的下标还原原始的 `URL`。
+
+## 代码
+
+```go
+package leetcode
+
+import (
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+type Codec struct {
+	urls []string
+}
+
+func Constructor() Codec {
+	return Codec{[]string{}}
+}
+
+// Encodes a URL to a shortened URL.
+func (this *Codec) encode(longUrl string) string {
+	this.urls = append(this.urls, longUrl)
+	return "http://tinyurl.com/" + fmt.Sprintf("%v", len(this.urls)-1)
+}
+
+// Decodes a shortened URL to its original URL.
+func (this *Codec) decode(shortUrl string) string {
+	tmp := strings.Split(shortUrl, "/")
+	i, _ := strconv.Atoi(tmp[len(tmp)-1])
+	return this.urls[i]
+}
+
+/**
+ * Your Codec object will be instantiated and called as such:
+ * obj := Constructor();
+ * url := obj.encode(longUrl);
+ * ans := obj.decode(url);
+ */
+```