{"board": "BBBoAAooooCoDDCo", "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: BBBoAAooooCoDDCo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "AAoooBBoCCDDEEFF", "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: AAoooBBoCCDDEEFF\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "BAAoBooCBooCDDDo", "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: BAAoBooCBooCDDDo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "BAAoBCDDECooEFFF", "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: BAAoBCDDECooEFFF\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "oAAoBoCCBDDoEEFF", "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: oAAoBoCCBDDoEEFF\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "oAAoBoCCBoooDDEE", "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: oAAoBoCCBoooDDEE\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "oAABCCCBDDDoEEoo", "size": 4, "moves": 2, "solution": ["Bv1", "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: oAABCCCBDDDoEEoo\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,A>1\n"]}}
{"board": "AAooBCCDBEEDFFoo", "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: AAooBCCDBEEDFFoo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "AAoBooCBooCooooo", "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: AAoBooCBooCooooo\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,A>2\n"]}}
{"board": "BCDEBCDEAAooFFGG", "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: BCDEBCDEAAooFFGG\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "BoooBCooBCooAAoo", "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: BoooBCooBCooAAoo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "AAooBBCCDDooooEE", "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: AAooBBCCDDooooEE\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>2\n"]}}
{"board": "BAACBooCDDECooEo", "size": 4, "moves": 2, "solution": ["Cv1", "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: BAACBooCDDECooEo\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nCv1,A>1\n"]}}
{"board": "BAAoBCDDBCEEFFoo", "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: BAAoBCDDBCEEFFoo\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "BoooBCooBCoDAAoD", "size": 4, "moves": 2, "solution": ["D^1", "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: BoooBCooBCoDAAoD\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nD^1,A>2\n"]}}
{"board": "oAABCDDBCEEBooFF", "size": 4, "moves": 3, "solution": ["F<1", "Bv1", "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: oAABCDDBCEEBooFF\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nF<1,Bv1,A>1\n"]}}
{"board": "AABCDoBCDoooEEEo", "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: AABCDoBCDoooEEEo\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,Bv1,A>2\n"]}}
{"board": "oAABCCCBoDDDEEEo", "size": 4, "moves": 3, "solution": ["D<1", "Bv1", "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: oAABCCCBoDDDEEEo\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Bv1,A>1\n"]}}
{"board": "oooooAABCCoBooDD", "size": 4, "moves": 3, "solution": ["D<1", "Bv1", "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: oooooAABCCoBooDD\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Bv1,A>1\n"]}}
{"board": "oBBBooCDooCDoAAD", "size": 4, "moves": 3, "solution": ["B<1", "D^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: oBBBooCDooCDoAAD\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nB<1,D^1,A>1\n"]}}
{"board": "AAoBCooBCoDDEEFF", "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: AAoBCooBCoDDEEFF\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Bv1,A>2\n"]}}
{"board": "oBBBoooCDDDCoAAC", "size": 4, "moves": 3, "solution": ["B<1", "C^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: oBBBoooCDDDCoAAC\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nB<1,C^1,A>1\n"]}}
{"board": "AAoBCCCBoDDDooEE", "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: AAoBCCCBoDDDooEE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Bv1,A>2\n"]}}
{"board": "oAABoCCBoDDDEEEo", "size": 4, "moves": 3, "solution": ["D<1", "Bv1", "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: oAABoCCBoDDDEEEo\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Bv1,A>1\n"]}}
{"board": "oBBBAAoCoooCoDDD", "size": 4, "moves": 3, "solution": ["D<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: oBBBAAoCoooCoDDD\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Cv1,A>2\n"]}}
{"board": "oBBBAAoCDDoCooEE", "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: oBBBAAoCDDoCooEE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nE<1,Cv1,A>2\n"]}}
{"board": "BCooBCoDoCEDAAED", "size": 4, "moves": 3, "solution": ["D^1", "E^1", "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: BCooBCoDoCEDAAED\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD^1,E^1,A>2\n"]}}
{"board": "oAABoCCBDDoBooEE", "size": 4, "moves": 3, "solution": ["E<1", "Bv1", "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: oAABoCCBDDoBooEE\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nE<1,Bv1,A>1\n"]}}
{"board": "oooBCAABCoDDCooo", "size": 4, "moves": 3, "solution": ["D<1", "Bv2", "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: oooBCAABCoDDCooo\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,Bv2,A>1\n"]}}
{"board": "oBBBCoooCAADoEED", "size": 4, "moves": 3, "solution": ["B<1", "D^2", "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: oBBBCoooCAADoEED\nOptimal length (moves): 3\nReturn only the and blocks.", "\nShortest path found.\n\n\nB<1,D^2,A>1\n"]}}
{"board": "AAoBoCCBDEEEDoFF", "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: AAoBoCCBDEEEDoFF\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": "AABCooBCoDoCoDEE", "size": 4, "moves": 5, "solution": ["Bv1", "D^1", "E<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: AABCooBCoDoCoDEE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,D^1,E<1,Bv1,A>2\n"]}}
{"board": "BCCCBooDAAoDoEEo", "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: BCCCBooDAAoDoEEo\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": "BBBCDAACDoooDEEE", "size": 4, "moves": 6, "solution": ["Cv1", "B>1", "C^1", "E<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: BBBCDAACDoooDEEE\nOptimal length (moves): 6\nReturn only the and blocks.", "\nShortest path found.\n\n\nCv1,B>1,C^1,E<1,Dv1,A>1\n"]}}
{"board": "BBBoCDDDCooEAAoE", "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: BBBoCDDDCooEAAoE\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": "oooBAAoBCDDDCEEE", "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: oooBAAoBCDDDCEEE\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": "AABCDEBCDEoCDFFF", "size": 4, "moves": 6, "solution": ["Bv1", "A>1", "C^1", "F<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: AABCDEBCDEoCDFFF\nOptimal length (moves): 6\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,A>1,C^1,F<1,Cv1,A>1\n"]}}
{"board": "ooBoAABCoDDCooEE", "size": 4, "moves": 5, "solution": ["D<1", "E<2", "Bv2", "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: ooBoAABCoDDCooEE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nD<1,E<2,Bv2,Bv1,A>2\n"]}}
{"board": "BCCCBDDDoAAEoooE", "size": 4, "moves": 5, "solution": ["Bv2", "B<1", "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: BCCCBDDDoAAEoooE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv2,B<1,C<1,E^2,A>1\n"]}}
{"board": "BCCCBooDBAADEEoo", "size": 4, "moves": 5, "solution": ["E>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: BCCCBooDBAADEEoo\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nE>1,Bv1,B<1,D^1,A>1\n"]}}
{"board": "oBBBCDDDCAAEoooE", "size": 4, "moves": 5, "solution": ["B<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: oBBBCDDDCAAEoooE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nB<1,Cv1,C<1,E^2,A>1\n"]}}
{"board": "AABCooBCDoBCDoEE", "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: AABCooBCDoBCDoEE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nD^1,E<2,Bv1,Bv1,A>2\n"]}}
{"board": "BCCCBDoEoDFEAAFE", "size": 4, "moves": 5, "solution": ["Bv1", "B<1", "E^1", "F^1", "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: BCCCBDoEoDFEAAFE\nOptimal length (moves): 5\nReturn only the and blocks.", "\nShortest path found.\n\n\nBv1,B<1,E^1,F^1,A>2\n"]}}
{"board": "BBBoAAoCDEECDFFF", "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: BBBoAAoCDEECDFFF\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": "AAoBCCoBDEEEDooo", "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: AAoBCCoBDEEEDooo\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": "oBAACoBDDCoEEEoooooFGGooF", "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: oBAACoBDDCoEEEoooooFGGooF\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nCv1,A>1\n"]}}
{"board": "BBBoooAAoCDDoECoFFECoGGoo", "size": 5, "moves": 2, "solution": ["Cv1", "A>2"], "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: BBBoooAAoCDDoECoFFECoGGoo\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nCv1,A>2\n"]}}
{"board": "AAooooooBoCCoBoDDEoFooEoF", "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: AAooooooBoCCoBoDDEoFooEoF\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>3\n"]}}
{"board": "oooBCDooBCDoAAoEEFFGooHHG", "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: oooBCDooBCDoAAoEEFFGooHHG\nOptimal length (moves): 1\nReturn only the and blocks.", "\nShortest path found.\n\n\nA>1\n"]}}
{"board": "BoCCCBDooEoDAAEoDFFoooooo", "size": 5, "moves": 2, "solution": ["Ev2", "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: BoCCCBDooEoDAAEoDFFoooooo\nOptimal length (moves): 2\nReturn only the and blocks.", "\nShortest path found.\n\n\nEv2,A>1\n"]}}
{"board": "BAAoCBoooCDDooooEEEFGGooF", "size": 5, "moves": 2, "solution": ["Cv1", "A>2"], "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: BAAoCBoooCDDooooEEEFGGooF\nOptimal length (moves): 2\nReturn only the and