rqb1kbnr/pp1p2pp/2n1pp2/8/PPp4P/N2P2PN/R1PBPP2/3QKB1R w Kkq - 5 10
FEN state: rqb1kbnr/pp1p2pp/2n1pp2/8/PPp4P/N2P2PN/R1PBPP2/3QKB1R w Kkq - 5 10 ; Best move: b4b5
The current state of the chess board is: Black rook at a8, black queen at b8, black bishop at c8, black king at e8, black bishop at f8, black knight at g8 and black rook at h8. Black pawn at a7, black pawn at b7, black pawn at d7, black pawn at g7 and black pawn at h7. Black knight at c6, black pawn at e6 and black pawn at f6. White pawn at a4, white pawn at b4, black pawn at c4 and white pawn at h4. White knight at a3, white pawn at d3, white pawn at g3 and white knight at h3. White rook at a2, white pawn at c2, white bishop at d2, white pawn at e2 and white pawn at f2. White queen at d1, white king at e1, white bishop at f1 and white rook at h1. White kingside, black kingside and black queenside castles are available. Half move number is 5. Full move number is 10. White to move.