Turochamp

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Turochamp is the name of a chess algorithm developed by Alan Turing and David Champernowne in 1948 . It was one of the first chess algorithms in the world.

functionality

In order to find the best move in a situation, the next two moves, i.e. your own move and the next move by your opponent, are usually checked; one also speaks of two half-moves. In special cases, however, further thought must be given. These are:

  • When a piece that was captured on the last move can be repulsed.
  • When a low-ranking piece can beat a higher-ranking piece.
  • When an unprotected piece can be captured.
  • When the opposing king can be checkmated .

In these cases you have to go through all possible moves until a position is reached that no longer has any of the above properties. All positions are then evaluated. This is done according to the following system:

  1. Material: For each figure, its material value is added to the position evaluation. Material values are for the farmer 1, for the Springer 3, for the runner 3.5, for the tower 5, for the lady 10 and the king 1000th
  2. Mobility: For all pieces except the pawns and the king, the square root of the number of permitted moves the piece can make is added to the evaluation. Strokes are counted twice
  3. Cover: If a rook, knight or bishop is simply covered, it gives one point. If he is doubly covered, there are 1.5 points.
  4. Mobility of the king: The square root of the number of permitted king moves without castling is added to the evaluation.
  5. King's Security: The number of possible moves a queen would have on the king's square is subtracted.
  6. Castling: If castling is still possible, one point is added to the assessment. Another point is added if castling is possible on the next move. Two points are also awarded if castling was made on the last move.
  7. Pawns: For each square that a pawn has moved, 0.2 is added. If a pawn is covered by at least one piece (apart from another pawn), the result is 0.3 points.
  8. Check and mate: a threat of checkmate results in one point, a check bid 0.5 points.

In the end, the algorithm decides on the move that leads to the best position with the highest value.

Games

There is only one known game that Turing played with this algorithm. One possible reason he stopped playing could be that it took about half an hour to calculate a single move. This meant that the game took over a week to complete. Turing played the following game in 1952 against his colleague Alick Glennie, a hobby player. Turing gave up the game when he lost the queen due to a bondage .

Turing's algorithm - Alick Glennie, Manchester 1952 (ECO code C26)
1. e4 e5 2. Nc3 Nf6 3. d4 Bb4 4. Nf3 d6 5. Bd2 Nc6 6. d5 Nd4 7. h4 Bg4 8. a4 Nxf3 + 9. gxf3 Bh5 10. Bb5 + c6 11. dxc6 0–0 12. cxb7 Rb8 13. Ba6 Qa5 14. Qe2 Nd7 15. Rg1 Nc5 16. Rg5 Bg6 17. Bb5 Nxb7 18. 0–0–0 Nc5 19. Bc6 Rfc8 20. Bd5 Bxc3 21. Bxc3 Qxa4 22. Kd2 Ne6 23.Rg4 Nd4 24. Qd3 Nb5 25.Bb3 Da6 26.Bc4 Bh5 27.Rg3 Da4 28.Bxb5 Qxb5 29.Qxd6 Rd8 0: 1

Programs

Alan Turing tried to program his algorithm into a Ferranti computer. However, he couldn't finish his job.

Individual evidence

  1. ↑ a b Jörg Bewersdorff : luck, logic and bluff: mathematics in play; Methods, results and limits . 3rd, revised. Ed. Vieweg, Wiesbaden 2003, ISBN 3-528-26997-9 .
  2. ↑ a b c chessprogramming - Turochamp. Retrieved July 11, 2018 .
  3. ↑ Dieter Steinweder, Frederic A. Friedel: Chess on the PC , market and technology, Haar b. Munich 1995, ISBN 3-87791-522-1 , pp. 33-35