FourSight

FourSight is a strong Connect 4 engine that can precisely analyze a position to a great depth but also provide good intuition in harder positions that can't be exhaustively analyzed. Human opponents might struggle to defeat even analysis depth 2!

Supported Commands

Use the following commands to interact:

• 2players: Start a two player game with a friend(No AI).
• go: Search (current position) indefinitely.
• go depth <d>: Search to depth <d> (e.g., go depth 20).
• go movetime <s>: Search for <s> milliseconds (e.g., go movetime 20000 searches for 20 seconds).
  • (The last depth calculation will continue over this time so you need to account for that.)
• position startpos: Clear the board.
• position <text>: Insert a position as a string.
  Example: position 2X4/2O4/7/7/7/7 adds an X and an O to the third column. Numbers count spaces and must be accurate(!).
  Dashes or other characters are just visual aids.
• add <ijk...>: Add integers i, j, k ... to internal state in one go. Example: add 445 will add to column 4 then 4 again then 5 in one go (any other character is ignored)"
• play: Start a game with the AI with default settings.
• play depth <d>: Start a game with the AI and make it search up to depth <d>.
• play movetime <s>: Start a game with the AI and make it search for <s> milliseconds.
• print: Print the current state.
• help: Show this help message.

In-game controls:

• Enter numbers 1-7 to play a column.
• Enter r to restart or q to quit.

Installation

To get started with FourSight, clone or download this repository:

git clone https://github.com/cyberterm/FourSight.git

You can use the provided makefile to compile:

make release

(a debug build is also provided with make)

Or directly compile with gcc from the main directory:

gcc -O3 -march=native -Iinclude src/*.c -o FourSight