{"board": "ooooAAooBCCoBDDD", "size": 4, "moves": 1, "solution": ["A>2"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: ooooAAooBCCoBDDD\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "oAAooooBCCoBoDDB", "size": 4, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oAAooooBCCoBoDDB\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "oAAoBCCoBDEEoDoo", "size": 4, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oAAoBCCoBDEEoDoo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "ooBoAABoCDoECDoE", "size": 4, "moves": 2, "solution": ["Bv2", "A>2"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: ooBoAABoCDoECDoE\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv2,A>2\n"]}}
{"board": "ooooAAooooooBBoo", "size": 4, "moves": 1, "solution": ["A>2"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: ooooAAooooooBBoo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "BCCCBoooDAAoDEEo", "size": 4, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BCCCBoooDAAoDEEo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "oooooBCDoBCDAAoo", "size": 4, "moves": 1, "solution": ["A>2"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oooooBCDoBCDAAoo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "BAAoBoCoBoCDEEoD", "size": 4, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BAAoBoCoBoCDEEoD\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "BoooBAAooCCCDDDo", "size": 4, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BoooBAAooCCCDDDo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "BoCDBoCDEFFFEAAo", "size": 4, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BoCDBoCDEFFFEAAo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "BBBoCAAoCooDCEED", "size": 4, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BBBoCAAoCooDCEED\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "AABooCBoDCooDEEE", "size": 4, "moves": 2, "solution": ["Bv1", "A>2"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AABooCBoDCooDEEE\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,A>2\n"]}}
{"board": "AAoooBCooBCoDDDo", "size": 4, "moves": 1, "solution": ["A>2"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AAoooBCooBCoDDDo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "BAAoBooooCCoDDDo", "size": 4, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BAAoBooooCCoDDDo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "AABCDDBCooBoEEoo", "size": 4, "moves": 3, "solution": ["Bv1", "Bv1", "A>2"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AABCDDBCooBoEEoo\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,Bv1,A>2\n"]}}
{"board": "BBBoAAoCDDDCoEEE", "size": 4, "moves": 3, "solution": ["E<1", "Cv1", "A>2"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BBBoAAoCDDDCoEEE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nE<1,Cv1,A>2\n"]}}
{"board": "AABoCCBoDDBEoFFE", "size": 4, "moves": 3, "solution": ["F<1", "Bv1", "A>2"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AABoCCBoDDBEoFFE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nF<1,Bv1,A>2\n"]}}
{"board": "BoooBAACDooCDoEE", "size": 4, "moves": 3, "solution": ["E<1", "Cv1", "A>1"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BoooBAACDooCDoEE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nE<1,Cv1,A>1\n"]}}
{"board": "oBBBoCCCDooEDAAE", "size": 4, "moves": 3, "solution": ["C<1", "E^1", "A>1"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oBBBoCCCDooEDAAE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nC<1,E^1,A>1\n"]}}
{"board": "oBBBCDEFCDEFCAAF", "size": 4, "moves": 3, "solution": ["B<1", "F^1", "A>1"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oBBBCDEFCDEFCAAF\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nB<1,F^1,A>1\n"]}}
{"board": "AAoBCCoBooDDoEEE", "size": 4, "moves": 3, "solution": ["D<1", "Bv1", "A>2"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AAoBCCoBooDDoEEE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Bv1,A>2\n"]}}
{"board": "AABCooBCooBooooo", "size": 4, "moves": 3, "solution": ["Bv1", "Bv1", "A>2"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AABCooBCooBooooo\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,Bv1,A>2\n"]}}
{"board": "AAoBoCCBooDDEEEo", "size": 4, "moves": 3, "solution": ["D<1", "Bv1", "A>2"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AAoBoCCBooDDEEEo\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Bv1,A>2\n"]}}
{"board": "oBBBoAACoooCoDDD", "size": 4, "moves": 3, "solution": ["D<1", "Cv1", "A>1"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oBBBoAACoooCoDDD\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Cv1,A>1\n"]}}
{"board": "BAACBoDCEEDCoFFF", "size": 4, "moves": 3, "solution": ["F<1", "Cv1", "A>1"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BAACBoDCEEDCoFFF\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nF<1,Cv1,A>1\n"]}}
{"board": "AAoBoooBooCCDDEE", "size": 4, "moves": 3, "solution": ["C<1", "Bv1", "A>2"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AAoBoooBooCCDDEE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nC<1,Bv1,A>2\n"]}}
{"board": "oAABCDDBCooBCEEE", "size": 4, "moves": 4, "solution": ["C^1", "E<1", "Cv1", "A>1"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oAABCDDBCooBCEEE\nOptimal length (moves): 4\nReturn only the and blocks.", "\nShortest path found.\n\n\nC^1,E<1,Cv1,A>1\n"]}}
{"board": "oooBAACBooCoDDoo", "size": 4, "moves": 3, "solution": ["Bv2", "Bv1", "A>2"], "difficulty": "medium", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oooBAACBooCoDDoo\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv2,Bv1,A>2\n"]}}
{"board": "oBBBCDDDCooEAAoE", "size": 4, "moves": 5, "solution": ["A>1", "Cv1", "C<1", "E^1", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oBBBCDDDCooEAAoE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,Cv1,C<1,E^1,A>1\n"]}}
{"board": "BBBCAAoCDoEEDFFF", "size": 4, "moves": 6, "solution": ["A>1", "D^1", "E<1", "F<1", "Cv2", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BBBCAAoCDoEEDFFF\nOptimal length (moves): 6\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,D^1,E<1,F<1,Cv2,A>1\n"]}}
{"board": "BoooBCCCAAoDoooD", "size": 4, "moves": 5, "solution": ["A>1", "Bv2", "B<1", "D^2", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BoooBCCCAAoDoooD\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,Bv2,B<1,D^2,A>1\n"]}}
{"board": "BBBoCDDDCAAEFFoE", "size": 4, "moves": 5, "solution": ["F>1", "Cv1", "C<1", "E^2", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BBBoCDDDCAAEFFoE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nF>1,Cv1,C<1,E^2,A>1\n"]}}
{"board": "BCCCBooDAAoDoooo", "size": 4, "moves": 5, "solution": ["A>1", "Bv1", "B<1", "D^1", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BCCCBooDAAoDoooo\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,Bv1,B<1,D^1,A>1\n"]}}
{"board": "AAoBCCoBDEEEDFFo", "size": 4, "moves": 6, "solution": ["A>1", "C>1", "D^2", "E<1", "Cv1", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AAoBCCoBDEEEDFFo\nOptimal length (moves): 6\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,C>1,D^2,E<1,Cv1,A>1\n"]}}
{"board": "oBBBAAoCDEECDFFF", "size": 4, "moves": 5, "solution": ["A>1", "D^1", "F<1", "Dv1", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oBBBAAoCDEECDFFF\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,D^1,F<1,Dv1,A>1\n"]}}
{"board": "oooBAAoBCDDDCoEE", "size": 4, "moves": 6, "solution": ["A>1", "C^2", "D<1", "E<1", "Cv2", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oooBAAoBCDDDCoEE\nOptimal length (moves): 6\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,C^2,D<1,E<1,Cv2,A>1\n"]}}
{"board": "AABCooBCoDBCoDEE", "size": 4, "moves": 5, "solution": ["D^1", "E<2", "Bv1", "Bv1", "A>2"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AABCooBCoDBCoDEE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nD^1,E<2,Bv1,Bv1,A>2\n"]}}
{"board": "BoooBCCCoooDAAoD", "size": 4, "moves": 5, "solution": ["A>1", "Bv2", "B<1", "D^1", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: BoooBCCCoooDAAoD\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,Bv2,B<1,D^1,A>1\n"]}}
{"board": "AAoBoCCBDEEEDFFF", "size": 4, "moves": 5, "solution": ["A>1", "D^2", "E<1", "Cv1", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AAoBoCCBDEEEDFFF\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1,D^2,E<1,Cv1,A>1\n"]}}
{"board": "AABCooBCoDBooDEE", "size": 4, "moves": 5, "solution": ["Cv1", "D^1", "E<2", "Bv1", "A>2"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AABCooBCoDBooDEE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nCv1,D^1,E<2,Bv1,A>2\n"]}}
{"board": "AABCDDBCoEECooFF", "size": 4, "moves": 5, "solution": ["E<1", "Bv1", "F<1", "Bv1", "A>2"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: AABCDDBCoEECooFF\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nE<1,Bv1,F<1,Bv1,A>2\n"]}}
{"board": "oooBCAABCDDDoEEE", "size": 4, "moves": 5, "solution": ["C^1", "D<1", "E<1", "Cv2", "A>1"], "difficulty": "hard", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (4×4) solver.\n\nInput: 16-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 4x4\nBoard: oooBCAABCDDDoEEE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nC^1,D<1,E<1,Cv2,A>1\n"]}}
{"board": "oBAACDBooCDEoooDEFFFoGGGo", "size": 5, "moves": 2, "solution": ["Cv1", "A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: oBAACDBooCDEoooDEFFFoGGGo\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nCv1,A>1\n"]}}
{"board": "AAoooBoCCCBDDEFoGGEFoHHHo", "size": 5, "moves": 1, "solution": ["A>3"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: AAoooBoCCCBDDEFoGGEFoHHHo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>3\n"]}}
{"board": "ooAAoBBBoCDEEECDooooFFGGo", "size": 5, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: ooAAoBBBoCDEEECDooooFFGGo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "BoAACBooDCEEFDoGHFDIGHJJI", "size": 5, "moves": 2, "solution": ["Cv1", "A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: BoAACBooDCEEFDoGHFDIGHJJI\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nCv1,A>1\n"]}}
{"board": "BCCCoBoAADEoFFDEoGHoooGHo", "size": 5, "moves": 2, "solution": ["Dv1", "A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: BCCCoBoAADEoFFDEoGHoooGHo\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nDv1,A>1\n"]}}
{"board": "oBAAooBCCoDBEEoDFGooDFGoo", "size": 5, "moves": 1, "solution": ["A>1"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: oBAAooBCCoDBEEoDFGooDFGoo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "AAooBCCDDBoooEBoFFEooGGoo", "size": 5, "moves": 2, "solution": ["Bv1", "A>3"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: AAooBCCDDBoooEBoFFEooGGoo\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,A>3\n"]}}
{"board": "BBBooAAoooCoDDDCooEEFFooo", "size": 5, "moves": 1, "solution": ["A>3"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: BBBooAAoooCoDDDCooEEFFooo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>3\n"]}}
{"board": "oBCoooBCoDAAooDoooEFGGoEF", "size": 5, "moves": 2, "solution": ["D^1", "A>3"], "difficulty": "easy", "messages": {"role": ["system", "user", "assistant"], "content": ["You are an expert Rush Hour (5×5) solver.\n\nInput: 25-char row-major board; 'o' empty, 'A' red 2-long horizontal, others B..Z (len 2/3; H/V).\nOutput exactly ONE optimal solution wrapped in tags:\n\n(brief internal reasoning)\n\n\ncomma,separated,move,list\n\nToken format: (A>2,B<1,Cv3). One move = slide any positive distance along axis.\nGoal: right end of 'A' reaches the right edge.\n", "Board size: 5x5\nBoard: oBCoooBCoDAAooDoooEFGGoEF\nOptimal length (moves): 2\nReturn only the and