r1bk2n1/p3qpb1/1pn4p/2P2p2/3Pp3/2B1P2Q/P1P3PP/RN2K2R w KQ - 0 21
FEN state: r1bk2n1/p3qpb1/1pn4p/2P2p2/3Pp3/2B1P2Q/P1P3PP/RN2K2R w KQ - 0 21 ; Best move: c5b6
The current state of the chess board is: Black rook at a8, black bishop at c8, black king at d8 and black knight at g8. Black pawn at a7, black queen at e7, black pawn at f7 and black bishop at g7. Black pawn at b6, black knight at c6 and black pawn at h6. White pawn at c5 and black pawn at f5. White pawn at d4 and black pawn at e4. White bishop at c3, white pawn at e3 and white queen at h3. White pawn at a2, white pawn at c2, white pawn at g2 and white pawn at h2. White rook at a1, white knight at b1, white king at e1 and white rook at h1. White kingside and white queenside castles are available. Half move number is 0. Full move number is 21. White to move.