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Null move pruning is cheating but at the same time it is not cheating.

Adding Null move pruning. Devblog#2

Chess engineChess botSoftware Development
What can I say?

Implementing null move pruning in chess AI – a seemingly straightforward task – revealed itself to be an intriguing puzzle. While the potential performance boost was enticing, the journey was riddled with challenges. Integrating it seamlessly with the existing alpha-beta pruning algorithm, balancing depth reduction for efficiency without sacrificing accuracy, and comprehending the trade-offs were crucial battles. Nevertheless, with perseverance, the challenges were conquered, and null move pruning became a valuable weapon in the AI's arsenal. This experience not only empowered the AI but also underscored the importance of understanding, meticulous implementation, and balancing efficiency with accuracy – all while reminding us that even the most serious pursuits can benefit from a touch of humor (think of a king dodging incoming attacks like Neo from The Matrix, but with a chessboard instead of bullets!).Null move pruning is a technique used in chess AI to optimize the minimax search algorithm. Imagine the AI analyzes moves for both players like exploring a branching tree. Null moves represent the opponent "passing their turn" and doing nothing.Here's how it works:

  1. Play a null move: The AI temporarily removes the "turn" requirement and simulates the opponent doing nothing.
  2. Evaluate deeply: Since the opponent didn't move, the AI can delve deeper into exploring its own best moves from this "null position."
  3. Negate the score: After analyzing deeper, the AI negates the score as it simulates minimizing the opponent's "non-move."
  4. Prune the branch: If the negated score is worse than the best alternative move already explored, the entire branch emanating from the null move is discarded, saving further exploration.

By selectively pruning branches based on the null move analysis, the AI focuses its search on more promising lines of play, ultimately making stronger decisions with limited resources.
Peace out guys. Next blog coming soon.
----------FreedBeast219