Fixing the indieflashblog address with archive.org since website has been discontinued (#500)

@lerignoux thank you!

README-ja.md

@@ -1620,7 +1620,7 @@ Notes
 | ランダムID発行システムの設計 | [blog.twitter.com](https://blog.twitter.com/2010/announcing-snowflake)<br/>[github.com](https://github.com/twitter/snowflake/) |
 | 一定のインターバル時間での上位k件を返す | [ucsb.edu](https://icmi.cs.ucsb.edu/research/tech_reports/reports/2005-23.pdf)<br/>[wpi.edu](http://davis.wpi.edu/xmdv/docs/EDBT11-diyang.pdf) |
 | 複数のデータセンターからデータを配信するサービスの設計 | [highscalability.com](http://highscalability.com/blog/2009/8/24/how-google-serves-data-from-multiple-datacenters.html) |
-| オンラインの複数プレイヤーカードゲームの設計 | [indieflashblog.com](http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)<br/>[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/) |
+| オンラインの複数プレイヤーカードゲームの設計 | [indieflashblog.com](https://web.archive.org/web/20180929181117/http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)<br/>[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/) |
 | ガーベッジコレクションシステムの設計 | [stuffwithstuff.com](http://journal.stuffwithstuff.com/2013/12/08/babys-first-garbage-collector/)<br/>[washington.edu](http://courses.cs.washington.edu/courses/csep521/07wi/prj/rick.pdf) |
 | システム設計例題を追加する | [Contribute](#contributing) |
 

README-zh-Hans.md

@@ -1631,7 +1631,7 @@ Notes
 | 设计一个随机 ID 生成系统          | [blog.twitter.com](https://blog.twitter.com/2010/announcing-snowflake)<br/>[github.com](https://github.com/twitter/snowflake/) |
 | 返回一定时间段内次数前 k 高的请求      | [ucsb.edu](https://icmi.cs.ucsb.edu/research/tech_reports/reports/2005-23.pdf)<br/>[wpi.edu](http://davis.wpi.edu/xmdv/docs/EDBT11-diyang.pdf) |
 | 设计一个数据源于多个数据中心的服务系统     | [highscalability.com](http://highscalability.com/blog/2009/8/24/how-google-serves-data-from-multiple-datacenters.html) |
-| 设计一个多人网络卡牌游戏            | [indieflashblog.com](http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)<br/>[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/) |
+| 设计一个多人网络卡牌游戏            | [indieflashblog.com](https://web.archive.org/web/20180929181117/http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)<br/>[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/) |
 | 设计一个垃圾回收系统              | [stuffwithstuff.com](http://journal.stuffwithstuff.com/2013/12/08/babys-first-garbage-collector/)<br/>[washington.edu](http://courses.cs.washington.edu/courses/csep521/07wi/prj/rick.pdf) |
 | 添加更多的系统设计问题             | [贡献](#贡献)              |
 

README-zh-TW.md

@@ -1621,7 +1621,7 @@ Notes
 | 設計一個隨機 ID 生成系統               | [blog.twitter.com](https://blog.twitter.com/2010/announcing-snowflake)<br/>[github.com](https://github.com/twitter/snowflake/)                                                                                                                                                                                                                                                                                                                         |
 | 給定一段時間，回傳次數排名前 K 的請求  | [ucsb.edu](https://icmi.cs.ucsb.edu/research/tech_reports/reports/2005-23.pdf)<br/>[wpi.edu](http://davis.wpi.edu/xmdv/docs/EDBT11-diyang.pdf)                                                                                                                                                                                                                                                                                                         |
 | 設計一個資料來源在多個資料中心的系統   | [highscalability.com](http://highscalability.com/blog/2009/8/24/how-google-serves-data-from-multiple-datacenters.html)                                                                                                                                                                                                                                                                                                                            |
-| 設計一個線上多人卡牌遊戲               | [indieflashblog.com](http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)<br/>[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/)                                                                                                                                                                                                                                                                       |
+| 設計一個線上多人卡牌遊戲               | [indieflashblog.com](https://web.archive.org/web/20180929181117/http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)<br/>[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/)                                                                                                                                                                                                                                                                       |
 | 設計一個垃圾回收系統                   | [stuffwithstuff.com](http://journal.stuffwithstuff.com/2013/12/08/babys-first-garbage-collector/)<br/>[washington.edu](http://courses.cs.washington.edu/courses/csep521/07wi/prj/rick.pdf)                                                                                                                                                                                                                                                             |
 | 貢獻更多系統設計問題                   | [Contribute](#如何貢獻)                                                                                                                                                                                                                                                                                                                                                                                                                           |
 

README.md

@@ -1670,7 +1670,7 @@ Handy metrics based on numbers above:
 | Design a random ID generation system | [blog.twitter.com](https://blog.twitter.com/2010/announcing-snowflake)<br/>[github.com](https://github.com/twitter/snowflake/) |
 | Return the top k requests during a time interval | [cs.ucsb.edu](https://www.cs.ucsb.edu/sites/cs.ucsb.edu/files/docs/reports/2005-23.pdf)<br/>[wpi.edu](http://davis.wpi.edu/xmdv/docs/EDBT11-diyang.pdf) |
 | Design a system that serves data from multiple data centers | [highscalability.com](http://highscalability.com/blog/2009/8/24/how-google-serves-data-from-multiple-datacenters.html) |
-| Design an online multiplayer card game | [indieflashblog.com](http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)<br/>[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/) |
+| Design an online multiplayer card game | [indieflashblog.com](https://web.archive.org/web/20180929181117/http://www.indieflashblog.com/how-to-create-an-asynchronous-multiplayer-game.html)<br/>[buildnewgames.com](http://buildnewgames.com/real-time-multiplayer/) |
 | Design a garbage collection system | [stuffwithstuff.com](http://journal.stuffwithstuff.com/2013/12/08/babys-first-garbage-collector/)<br/>[washington.edu](http://courses.cs.washington.edu/courses/csep521/07wi/prj/rick.pdf) |
 | Design an API rate limiter | [https://stripe.com/blog/](https://stripe.com/blog/rate-limiters) |
 | Design a Stock Exchange (like NASDAQ or Binance) | [Jane Street](https://youtu.be/b1e4t2k2KJY)<br/>[Golang Implementation](https://around25.com/blog/building-a-trading-engine-for-a-crypto-exchange/)<br/>[Go Implemenation](http://bhomnick.net/building-a-simple-limit-order-in-go/) |