The code attempts to be faithful to the basic rules:

- Select a COLUMN by selecting the X (ENTER)

- Select a ROW by selecting the Y (ENTER)

- Complete your selection by identifying the SIDE as A, B, C, D (ENTER)

The game progresses with YOU and the COMPUTER taking alternate turns. As the choices diminish, the game becomes more difficult and the number of open sides (those that do not close a box, become less numerous.) Eventually a box will have all 4 sides closed by either YOU or the COMPUTER and that box then gets counted on the scoreboard. Closing all 4 sides of a box entitles a free move.

The goal is to win by completing more boxes than the computer.

Good luck.

ONLINE RULES  DOTS and BOXES

CAVEATS: Depending on YOUR Windows security configuration,

- you may not be able to download the ZIP

- your Windows security may delete the dots.exe executable

- your Windows security may delete the dots.bas source code. Use dots.txt instead.

There are numerous solutions like adding an exception to the "Virus & threat protection settings", but I am not going to go into details because of the potential consequences of changing the default Windows security policies. YouTube and online discussions are easily found. See Gallery where I created a file exemption that provides the "Run anyways" choice.

If you are having difficulties, you can easily download the QB64 IDE and just run the downloadable dos.bas source code:  QB64 Here