April 30, 2020

Setting Up The Topcoder Java Applet Arena & Kawigi Editor

Setting up the Applet

Installing Java Runtime Environment

  • Download the latest version of JRE (Java Runtime Environment).

  • Follow this guide to set up the environment for Java.

  • Download the Topcoder Applet

  • It is recommended that you move the downloaded file to a folder of its own called “Topcoder Applet”.

  • Click on the file to launch the Applet.

  • Note: if you are using Mac OS you will have to right-click and then open. It will prompt you with ““ContestAppletProd.jnlp” is from an unidentified developer. Are you sure you want to open it?” . Select Open.

Solving Java Security Warning

If you get a security warning after installing Java, add Topcoder to the exception site list:

WindowsControl Panel → Java → Security → Exception List
OSXSystem Preferences → Java → Security → Exception List
LInux, Unix, Solaris, FreeBSD1. Open a terminal and execute the following command: /usr/bin/jdk1.8.0_05/bin/ControlPanel
2. Replace /usr/bin/jdk1.8.0_05 by the path of your Java installation.

Here are the exceptions you have to add:



Once completed open the Topcoder Applet again and enter your Topcoder handle (username) and password.


You should see the following screen once you have logged in.


Check out this How To Compete Guide to learn how to get started with practicing and competing inside the Topcoder Java Applet.

Setting up the KawigiEdit Plugin (optional)

This plugin is very useful and could save you time during SRM competitions. Remember that your score is based on the time it takes you to complete the problem.

The Topcoder Arena does not rely on standard IO.  It requires a function inside of a class and this function takes the parameters as the input and returns the output.

Fortunately, KawigiEdit does most of this for us, so just choose your prefered language from the top (C++ in our case) and get back to the code area below.

Once you install KawigiEdit your editor window will look like this:


The KawigiEdit plugin has plenty of features, but we will only discuss some of them and how to set it up properly.

  • Download the plugin

  • It’s recommended that you put the file in the same directory of the Arena (in the “Topcoder Arena” folder from earlier)

  • Start the Topcoder Arena Applet (if it is not already running).

  • From the options menu, choose “Editor”.  The editor preferences dialog should come up.


  • Click on the “Add” button and a dialog titled “Enter Plugin Information” should pop up.


  • Fill in the fields with the following information:
    Name : “KawigiEdit”
    EntryPoint : “kawigi.KawigiEdit”

  • Click on “Browse” and navigate to your “Topcoder Applet” folder and select the KawigiEdit_x.jar file.

  • Click OK and return to the Editor Preferences dialog.

  • Check the “Default” box on the KawigiEdit line.

  • Click “Save” and close.

Group 9
Group 9