Added 0535-encode-and-decode-tinyurl.cs

Author: Dalton-V

csharp/0535-encode-and-decode-tinyurl.cs

@@ -0,0 +1,29 @@
+public class Codec
+{
+    public Dictionary<string, string> EncodeMap = new Dictionary<string, string>();
+    public Dictionary<string, string> DecodeMap = new Dictionary<string, string>();
+    public string Base = "http://tinyurl.com/";
+
+    // Encodes a URL to a shortened URL
+    public string encode(string longUrl)
+    {
+        if (!EncodeMap.ContainsKey(longUrl))
+        {
+            var shortUrl = Base + EncodeMap.Count().ToString();
+            EncodeMap.Add(longUrl, shortUrl);
+            DecodeMap.Add(shortUrl, longUrl);
+        }
+
+        return EncodeMap[longUrl];
+    }
+
+    // Decodes a shortened URL to its original URL.
+    public string decode(string shortUrl)
+    {
+        return DecodeMap[shortUrl];
+    }
+}
+
+// Your Codec object will be instantiated and called as such:
+// Codec codec = new Codec();
+// codec.decode(codec.encode(url));