This is an old implementation of the game Battleships that I wrote back in 2009. It's a bit cludgy and there are a few things I never got around to implementing (Salvos game mode, LAN multiplayer) and it uses the old WinBGIm library which I had always meant to swap out for something better, eg. allegro or something.
There are no warranties or licenses or anything, so feel free to take it and break it.