#include #include #ifndef RJ //#define RJ // Uncheck for debugging #endif int q, // Number of unsolved Cell positions Board wise r[81], // Used for sorting and eliminating unsolved Cell positions s[81], // Sudoku solved 81 Cell positions Board wise g[81], // Bitwise Candidates for each unsolved Cell positions Board wise n[3]; // Number of Naked Singles, Hidden Singles and Guesses Board wise static int b[512] = { // Bitwise Candidates 0, 1, 2, 12, 3, 13, 23, 123, 4, 14, 24, 124, 34, 134, 234, 1234, 5, 15, 25, 125, 35, 135, 235, 1235, 45, 145, 245, 1245, 345, 1345, 2345, 12345, 6, 16, 26, 126, 36, 136, 236, 1236, 46, 146, 246, 1246, 346, 1346, 2346, 12346, 56, 156, 256, 1256, 356, 1356, 2356, 12356, 456, 1456, 2456, 12456, 3456, 13456, 23456, 123456, 7, 17, 27, 127, 37, 137, 237, 1237, 47, 147, 247, 1247, 347, 1347, 2347, 12347, 57, 157, 257, 1257, 357, 1357, 2357, 12357, 457, 1457, 2457, 12457, 3457, 13457, 23457, 123457, 67, 167, 267, 1267, 367, 1367, 2367, 12367, 467, 1467, 2467, 12467, 3467, 13467, 23467, 123467, 567, 1567, 2567, 12567, 3567, 13567, 23567, 123567, 4567, 14567, 24567, 124567, 34567, 134567, 234567, 1234567, 8, 18, 28, 128, 38, 138, 238, 1238, 48, 148, 248, 1248, 348, 1348, 2348, 12348, 58, 158, 258, 1258, 358, 1358, 2358, 12358, 458, 1458, 2458, 12458, 3458, 13458, 23458, 123458, 68, 168, 268, 1268, 368, 1368, 2368, 12368, 468, 1468, 2468, 12468, 3468, 13468, 23468, 123468, 568, 1568, 2568, 12568, 3568, 13568, 23568, 123568, 4568, 14568, 24568, 124568, 34568, 134568, 234568, 1234568, 78, 178, 278, 1278, 378, 1378, 2378, 12378, 478, 1478, 2478, 12478, 3478, 13478, 23478, 123478, 578, 1578, 2578, 12578, 3578, 13578, 23578, 123578, 4578, 14578, 24578, 124578, 34578, 134578, 234578, 1234578, 378, 1678, 2678, 12678, 3678, 13678, 23678, 123678, 4678, 14678, 24678, 124678, 34678, 134678, 234678, 1234678, 5678, 15678, 25678, 125678, 35678, 135678, 235678, 1235678, 45678, 145678, 245678, 1245678, 345678, 1345678, 2345678, 12345678, 9, 19, 29, 129, 39, 139, 239, 1239, 49, 149, 249, 1249, 349, 1349, 2349, 12349, 59, 159, 259, 1259, 359, 1359, 2359, 12359, 459, 1459, 2459, 12459, 3459, 13459, 23459, 123459, 69, 169, 269, 1269, 369, 1369, 2369, 12369, 469, 1469, 2469, 12469, 3469, 13469, 23469, 123469, 569, 1569, 2569, 12569, 3569, 13569, 23569, 123569, 4569, 14569, 24569, 124569, 34569, 134569, 234569, 1234569, 79, 179, 279, 1279, 379, 1379, 2379, 12379, 479, 1479, 2479, 12479, 3479, 13479, 23479, 123479, 579, 1579, 2579, 12579, 3579, 13579, 23579, 123579, 4579, 14579, 24579, 124579, 34579, 134579, 234579, 1234579, 679, 1679, 2679, 12679, 3679, 13679, 23679, 123679, 4679, 14679, 24679, 124679, 34679, 134679, 234679, 1234679, 5679, 15679, 25679, 125679, 35679, 135679, 235679, 1235679, 45679, 145679, 245679, 1245679, 345679, 1345679, 2345679, 12345679, 89, 189, 289, 1289, 389, 1389, 2389, 12389, 489, 1489, 2489, 12489, 3489, 13489, 23489, 123489, 589, 1589, 2589, 12589, 3589, 13589, 23589, 123589, 4589, 14589, 24589, 124589, 34589, 134589, 234589, 1234589, 689, 1689, 2689, 12689, 3689, 13689, 23689, 123689, 4689, 14689, 24689, 124689, 34689, 134689, 234689, 1234689, 5689, 15689, 25689, 125689, 35689, 135689, 235689, 1235689, 45689, 145689, 245689, 1245689, 345689, 1345689, 2345689, 12345689, 789, 1789, 2789, 12789, 3789, 13789, 23789, 123789, 4789, 14789, 24789, 124789, 34789, 134789, 234789, 1234789, 5789, 15789, 25789, 125789, 35789, 135789, 235789, 1235789, 45789, 145789, 245789, 1245789, 345789, 1345789, 2345789, 12345789, 6789, 16789, 26789, 126789, 36789, 136789, 236789, 1236789, 46789, 146789, 246789, 1246789, 346789, 1346789, 2346789, 12346789, 56789, 156789, 256789, 1256789, 356789, 1356789, 2356789, 12356789, 456789, 1456789, 2456789, 12456789, 3456789, 13456789, 23456789,123456789}, B[513] = { // Bit Count 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8, 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8, 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8, 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8, 5, 6, 6, 7, 6, 7, 7, 8, 6, 7, 7, 8, 7, 8, 8, 9,10}, w[81][20] = { // Affected unsolved 20 Cell positions { 3, 4, 5, 6, 7, 8, 1, 2,10,11,19,20, 9,18,27,36,45,54,63,72}, { 3, 4, 5, 6, 7, 8, 0, 2, 9,11,18,20,10,19,28,37,46,55,64,73}, { 3, 4, 5, 6, 7, 8, 0, 1, 9,10,18,19,11,20,29,38,47,56,65,74}, { 0, 1, 2, 6, 7, 8, 4, 5,13,14,22,23,12,21,30,39,48,57,66,75}, { 0, 1, 2, 6, 7, 8, 3, 5,12,14,21,23,13,22,31,40,49,58,67,76}, { 0, 1, 2, 6, 7, 8, 3, 4,12,13,21,22,14,23,32,41,50,59,68,77}, { 0, 1, 2, 3, 4, 5, 7, 8,16,17,25,26,15,24,33,42,51,60,69,78}, { 0, 1, 2, 3, 4, 5, 6, 8,15,17,24,26,16,25,34,43,52,61,70,79}, { 0, 1, 2, 3, 4, 5, 6, 7,15,16,24,25,17,26,35,44,53,62,71,80}, {12,13,14,15,16,17,10,11, 1, 2,19,20, 0,18,27,36,45,54,63,72}, {12,13,14,15,16,17, 9,11, 0, 2,18,20, 1,19,28,37,46,55,64,73}, {12,13,14,15,16,17, 9,10, 0, 1,18,19, 2,20,29,38,47,56,65,74}, { 9,10,11,15,16,17,13,14, 4, 5,22,23, 3,21,30,39,48,57,66,75}, { 9,10,11,15,16,17,12,14, 3, 5,21,23, 4,22,31,40,49,58,67,76}, { 9,10,11,15,16,17,12,13, 3, 4,21,22, 5,23,32,41,50,59,68,77}, { 9,10,11,12,13,14,16,17, 7, 8,25,26, 6,24,33,42,51,60,69,78}, { 9,10,11,12,13,14,15,17, 6, 8,24,26, 7,25,34,43,52,61,70,79}, { 9,10,11,12,13,14,15,16, 6, 7,24,25, 8,26,35,44,53,62,71,80}, {21,22,23,24,25,26,19,20, 1, 2,10,11, 0, 9,27,36,45,54,63,72}, {21,22,23,24,25,26,18,20, 0, 2, 9,11, 1,10,28,37,46,55,64,73}, {21,22,23,24,25,26,18,19, 0, 1, 9,10, 2,11,29,38,47,56,65,74}, {18,19,20,24,25,26,22,23, 4, 5,13,14, 3,12,30,39,48,57,66,75}, {18,19,20,24,25,26,21,23, 3, 5,12,14, 4,13,31,40,49,58,67,76}, {18,19,20,24,25,26,21,22, 3, 4,12,13, 5,14,32,41,50,59,68,77}, {18,19,20,21,22,23,25,26, 7, 8,16,17, 6,15,33,42,51,60,69,78}, {18,19,20,21,22,23,24,26, 6, 8,15,17, 7,16,34,43,52,61,70,79}, {18,19,20,21,22,23,24,25, 6, 7,15,16, 8,17,35,44,53,62,71,80}, {30,31,32,33,34,35,28,29,37,38,46,47,36,45, 0, 9,18,54,63,72}, {30,31,32,33,34,35,27,29,36,38,45,47,37,46, 1,10,19,55,64,73}, {30,31,32,33,34,35,27,28,36,37,45,46,38,47, 2,11,20,56,65,74}, {27,28,29,33,34,35,31,32,40,41,49,50,39,48, 3,12,21,57,66,75}, {27,28,29,33,34,35,30,32,39,41,48,50,40,49, 4,13,22,58,67,76}, {27,28,29,33,34,35,30,31,39,40,48,49,41,50, 5,14,23,59,68,77}, {27,28,29,30,31,32,34,35,43,44,52,53,42,51, 6,15,24,60,69,78}, {27,28,29,30,31,32,33,35,42,44,51,53,43,52, 7,16,25,61,70,79}, {27,28,29,30,31,32,33,34,42,43,51,52,44,53, 8,17,26,62,71,80}, {39,40,41,42,43,44,37,38,28,29,46,47,27,45, 0, 9,18,54,63,72}, {39,40,41,42,43,44,36,38,27,29,45,47,28,46, 1,10,19,55,64,73}, {39,40,41,42,43,44,36,37,27,28,45,46,29,47, 2,11,20,56,65,74}, {36,37,38,42,43,44,40,41,31,32,49,50,30,48, 3,12,21,57,66,75}, {36,37,38,42,43,44,39,41,30,32,48,50,31,49, 4,13,22,58,67,76}, {36,37,38,42,43,44,39,40,30,31,48,49,32,50, 5,14,23,59,68,77}, {36,37,38,39,40,41,43,44,34,35,52,53,33,51, 6,15,24,60,69,78}, {36,37,38,39,40,41,42,44,33,35,51,53,34,52, 7,16,25,61,70,79}, {36,37,38,39,40,41,42,43,33,34,51,52,35,53, 8,17,26,62,71,80}, {48,49,50,51,52,53,46,47,28,29,37,38,27,36, 0, 9,18,54,63,72}, {48,49,50,51,52,53,45,47,27,29,36,38,28,37, 1,10,19,55,64,73}, {48,49,50,51,52,53,45,46,27,28,36,37,29,38, 2,11,20,56,65,74}, {45,46,47,51,52,53,49,50,31,32,40,41,30,39, 3,12,21,57,66,75}, {45,46,47,51,52,53,48,50,30,32,39,41,31,40, 4,13,22,58,67,76}, {45,46,47,51,52,53,48,49,30,31,39,40,32,41, 5,14,23,59,68,77}, {45,46,47,48,49,50,52,53,34,35,43,44,33,42, 6,15,24,60,69,78}, {45,46,47,48,49,50,51,53,33,35,42,44,34,43, 7,16,25,61,70,79}, {45,46,47,48,49,50,51,52,33,34,42,43,35,44, 8,17,26,62,71,80}, {57,58,59,60,61,62,55,56,64,65,73,74,63,72, 0, 9,18,27,36,45}, {57,58,59,60,61,62,54,56,63,65,72,74,64,73, 1,10,19,28,37,46}, {57,58,59,60,61,62,54,55,63,64,72,73,65,74, 2,11,20,29,38,47}, {54,55,56,60,61,62,58,59,67,68,76,77,66,75, 3,12,21,30,39,48}, {54,55,56,60,61,62,57,59,66,68,75,77,67,76, 4,13,22,31,40,49}, {54,55,56,60,61,62,57,58,66,67,75,76,68,77, 5,14,23,32,41,50}, {54,55,56,57,58,59,61,62,70,71,79,80,69,78, 6,15,24,33,42,51}, {54,55,56,57,58,59,60,62,69,71,78,80,70,79, 7,16,25,34,43,52}, {54,55,56,57,58,59,60,61,69,70,78,79,71,80, 8,17,26,35,44,53}, {66,67,68,69,70,71,64,65,55,56,73,74,54,72, 0, 9,18,27,36,45}, {66,67,68,69,70,71,63,65,54,56,72,74,55,73, 1,10,19,28,37,46}, {66,67,68,69,70,71,63,64,54,55,72,73,56,74, 2,11,20,29,38,47}, {63,64,65,69,70,71,67,68,58,59,76,77,57,75, 3,12,21,30,39,48}, {63,64,65,69,70,71,66,68,57,59,75,77,58,76, 4,13,22,31,40,49}, {63,64,65,69,70,71,66,67,57,58,75,76,59,77, 5,14,23,32,41,50}, {63,64,65,66,67,68,70,71,61,62,79,80,60,78, 6,15,24,33,42,51}, {63,64,65,66,67,68,69,71,60,62,78,80,61,79, 7,16,25,34,43,52}, {63,64,65,66,67,68,69,70,60,61,78,79,62,80, 8,17,26,35,44,53}, {75,76,77,78,79,80,73,74,55,56,64,65,54,63, 0, 9,18,27,36,45}, {75,76,77,78,79,80,72,74,54,56,63,65,55,64, 1,10,19,28,37,46}, {75,76,77,78,79,80,72,73,54,55,63,64,56,65, 2,11,20,29,38,47}, {72,73,74,78,79,80,76,77,58,59,67,68,57,66, 3,12,21,30,39,48}, {72,73,74,78,79,80,75,77,57,59,66,68,58,67, 4,13,22,31,40,49}, {72,73,74,78,79,80,75,76,57,58,66,67,59,68, 5,14,23,32,41,50}, {72,73,74,75,76,77,79,80,61,62,70,71,60,69, 6,15,24,33,42,51}, {72,73,74,75,76,77,78,80,60,62,69,71,61,70, 7,16,25,34,43,52}, {72,73,74,75,76,77,78,79,60,61,69,70,62,71, 8,17,26,35,44,53}}, l[27][9] = { // Unit Cell positions for Naked/Hidden tuples { 0, 1, 2, 3, 4, 5, 6, 7, 8}, { 9,10,11,12,13,14,15,16,17}, {18,19,20,21,22,23,24,25,26}, {27,28,29,30,31,32,33,34,35}, {36,37,38,39,40,41,42,43,44}, {45,46,47,48,49,50,51,52,53}, {54,55,56,57,58,59,60,61,62}, {63,64,65,66,67,68,69,70,71}, {72,73,74,75,76,77,78,79,80}, { 0, 9,18,27,36,45,54,63,72}, { 1,10,19,28,37,46,55,64,73}, { 2,11,20,29,38,47,56,65,74}, { 3,12,21,30,39,48,57,66,75}, { 4,13,22,31,40,49,58,67,76}, { 5,14,23,32,41,50,59,68,77}, { 6,15,24,33,42,51,60,69,78}, { 7,16,25,34,43,52,61,70,79}, { 8,17,26,35,44,53,62,71,80}, { 0, 1, 2, 9,10,11,18,19,20}, { 3, 4, 5,12,13,14,21,22,23}, { 6, 7, 8,15,16,17,24,25,26}, {27,28,29,36,37,38,45,46,47}, {30,31,32,39,40,41,48,49,50}, {33,34,35,42,43,44,51,52,53}, {54,55,56,63,64,65,72,73,74}, {57,58,59,66,67,68,75,76,77}, {60,61,62,69,70,71,78,79,80}}, h[246][9] = { // 36 pairs/84 triplets/126 quads Cell positions first then Unit other Cell positions { 0, 1, 2, 3, 4, 5, 6, 7, 8}, { 0, 2, 1, 3, 4, 5, 6, 7, 8}, { 0, 3, 1, 2, 4, 5, 6, 7, 8}, { 0, 4, 1, 2, 3, 5, 6, 7, 8}, { 0, 5, 1, 2, 3, 4, 6, 7, 8}, { 0, 6, 1, 2, 3, 4, 5, 7, 8}, { 0, 7, 1, 2, 3, 4, 5, 6, 8}, { 0, 8, 1, 2, 3, 4, 5, 6, 7}, { 1, 2, 0, 3, 4, 5, 6, 7, 8}, { 1, 3, 0, 2, 4, 5, 6, 7, 8}, { 1, 4, 0, 2, 3, 5, 6, 7, 8}, { 1, 5, 0, 2, 3, 4, 6, 7, 8}, { 1, 6, 0, 2, 3, 4, 5, 7, 8}, { 1, 7, 0, 2, 3, 4, 5, 6, 8}, { 1, 8, 0, 2, 3, 4, 5, 6, 7}, { 2, 3, 0, 1, 4, 5, 6, 7, 8}, { 2, 4, 0, 1, 3, 5, 6, 7, 8}, { 2, 5, 0, 1, 3, 4, 6, 7, 8}, { 2, 6, 0, 1, 3, 4, 5, 7, 8}, { 2, 7, 0, 1, 3, 4, 5, 6, 8}, { 2, 8, 0, 1, 3, 4, 5, 6, 7}, { 3, 4, 0, 1, 2, 5, 6, 7, 8}, { 3, 5, 0, 1, 2, 4, 6, 7, 8}, { 3, 6, 0, 1, 2, 4, 5, 7, 8}, { 3, 7, 0, 1, 2, 4, 5, 6, 8}, { 3, 8, 0, 1, 2, 4, 5, 6, 7}, { 4, 5, 0, 1, 2, 3, 6, 7, 8}, { 4, 6, 0, 1, 2, 3, 5, 7, 8}, { 4, 7, 0, 1, 2, 3, 5, 6, 8}, { 4, 8, 0, 1, 2, 3, 5, 6, 7}, { 5, 6, 0, 1, 2, 3, 4, 7, 8}, { 5, 7, 0, 1, 2, 3, 4, 6, 8}, { 5, 8, 0, 1, 2, 3, 4, 6, 7}, { 6, 7, 0, 1, 2, 3, 4, 5, 8}, { 6, 8, 0, 1, 2, 3, 4, 5, 7}, { 7, 8, 0, 1, 2, 3, 4, 5, 6}, { 0, 1, 2, 3, 4, 5, 6, 7, 8}, { 0, 1, 3, 2, 4, 5, 6, 7, 8}, { 0, 1, 4, 2, 3, 5, 6, 7, 8}, { 0, 1, 5, 2, 3, 4, 6, 7, 8}, { 0, 1, 6, 2, 3, 4, 5, 7, 8}, { 0, 1, 7, 2, 3, 4, 5, 6, 8}, { 0, 1, 8, 2, 3, 4, 5, 6, 7}, { 0, 2, 3, 1, 4, 5, 6, 7, 8}, { 0, 2, 4, 1, 3, 5, 6, 7, 8}, { 0, 2, 5, 1, 3, 4, 6, 7, 8}, { 0, 2, 6, 1, 3, 4, 5, 7, 8}, { 0, 2, 7, 1, 3, 4, 5, 6, 8}, { 0, 2, 8, 1, 3, 4, 5, 6, 7}, { 0, 3, 4, 1, 2, 5, 6, 7, 8}, { 0, 3, 5, 1, 2, 4, 6, 7, 8}, { 0, 3, 6, 1, 2, 4, 5, 7, 8}, { 0, 3, 7, 1, 2, 4, 5, 6, 8}, { 0, 3, 8, 1, 2, 4, 5, 6, 7}, { 0, 4, 5, 1, 2, 3, 6, 7, 8}, { 0, 4, 6, 1, 2, 3, 5, 7, 8}, { 0, 4, 7, 1, 2, 3, 5, 6, 8}, { 0, 4, 8, 1, 2, 3, 5, 6, 7}, { 0, 5, 6, 1, 2, 3, 4, 7, 8}, { 0, 5, 7, 1, 2, 3, 4, 6, 8}, { 0, 5, 8, 1, 2, 3, 4, 6, 7}, { 0, 6, 7, 1, 2, 3, 4, 5, 8}, { 0, 6, 8, 1, 2, 3, 4, 5, 7}, { 0, 7, 8, 1, 2, 3, 4, 5, 6}, { 1, 2, 3, 0, 4, 5, 6, 7, 8}, { 1, 2, 4, 0, 3, 5, 6, 7, 8}, { 1, 2, 5, 0, 3, 4, 6, 7, 8}, { 1, 2, 6, 0, 3, 4, 5, 7, 8}, { 1, 2, 7, 0, 3, 4, 5, 6, 8}, { 1, 2, 8, 0, 3, 4, 5, 6, 7}, { 1, 3, 4, 0, 2, 5, 6, 7, 8}, { 1, 3, 5, 0, 2, 4, 6, 7, 8}, { 1, 3, 6, 0, 2, 4, 5, 7, 8}, { 1, 3, 7, 0, 2, 4, 5, 6, 8}, { 1, 3, 8, 0, 2, 4, 5, 6, 7}, { 1, 4, 5, 0, 2, 3, 6, 7, 8}, { 1, 4, 6, 0, 2, 3, 5, 7, 8}, { 1, 4, 7, 0, 2, 3, 5, 6, 8}, { 1, 4, 8, 0, 2, 3, 5, 6, 7}, { 1, 5, 6, 0, 2, 3, 4, 7, 8}, { 1, 5, 7, 0, 2, 3, 4, 6, 8}, { 1, 5, 8, 0, 2, 3, 4, 6, 7}, { 1, 6, 7, 0, 2, 3, 4, 5, 8}, { 1, 6, 8, 0, 2, 3, 4, 5, 7}, { 1, 7, 8, 0, 2, 3, 4, 5, 6}, { 2, 3, 4, 0, 1, 5, 6, 7, 8}, { 2, 3, 5, 0, 1, 4, 6, 7, 8}, { 2, 3, 6, 0, 1, 4, 5, 7, 8}, { 2, 3, 7, 0, 1, 4, 5, 6, 8}, { 2, 3, 8, 0, 1, 4, 5, 6, 7}, { 2, 4, 5, 0, 1, 3, 6, 7, 8}, { 2, 4, 6, 0, 1, 3, 5, 7, 8}, { 2, 4, 7, 0, 1, 3, 5, 6, 8}, { 2, 4, 8, 0, 1, 3, 5, 6, 7}, { 2, 5, 6, 0, 1, 3, 4, 7, 8}, { 2, 5, 7, 0, 1, 3, 4, 6, 8}, { 2, 5, 8, 0, 1, 3, 4, 6, 7}, { 2, 6, 7, 0, 1, 3, 4, 5, 8}, { 2, 6, 8, 0, 1, 3, 4, 5, 7}, { 2, 7, 8, 0, 1, 3, 4, 5, 6}, { 3, 4, 5, 0, 1, 2, 6, 7, 8}, { 3, 4, 6, 0, 1, 2, 5, 7, 8}, { 3, 4, 7, 0, 1, 2, 5, 6, 8}, { 3, 4, 8, 0, 1, 2, 5, 6, 7}, { 3, 5, 6, 0, 1, 2, 4, 7, 8}, { 3, 5, 7, 0, 1, 2, 4, 6, 8}, { 3, 5, 8, 0, 1, 2, 4, 6, 7}, { 3, 6, 7, 0, 1, 2, 4, 5, 8}, { 3, 6, 8, 0, 1, 2, 4, 5, 7}, { 3, 7, 8, 0, 1, 2, 4, 5, 6}, { 4, 5, 6, 0, 1, 2, 3, 7, 8}, { 4, 5, 7, 0, 1, 2, 3, 6, 8}, { 4, 5, 8, 0, 1, 2, 3, 6, 7}, { 4, 6, 7, 0, 1, 2, 3, 5, 8}, { 4, 6, 8, 0, 1, 2, 3, 5, 7}, { 4, 7, 8, 0, 1, 2, 3, 5, 6}, { 5, 6, 7, 0, 1, 2, 3, 4, 8}, { 5, 6, 8, 0, 1, 2, 3, 4, 7}, { 5, 7, 8, 0, 1, 2, 3, 4, 6}, { 6, 7, 8, 0, 1, 2, 3, 4, 5}, { 0, 1, 2, 3, 4, 5, 6, 7, 8}, { 0, 1, 2, 4, 3, 5, 6, 7, 8}, { 0, 1, 2, 5, 3, 4, 6, 7, 8}, { 0, 1, 2, 6, 3, 4, 5, 7, 8}, { 0, 1, 2, 7, 3, 4, 5, 6, 8}, { 0, 1, 2, 8, 3, 4, 5, 6, 7}, { 0, 1, 3, 4, 2, 5, 6, 7, 8}, { 0, 1, 3, 5, 2, 4, 6, 7, 8}, { 0, 1, 3, 6, 2, 4, 5, 7, 8}, { 0, 1, 3, 7, 2, 4, 5, 6, 8}, { 0, 1, 3, 8, 2, 4, 5, 6, 7}, { 0, 1, 4, 5, 2, 3, 6, 7, 8}, { 0, 1, 4, 6, 2, 3, 5, 7, 8}, { 0, 1, 4, 7, 2, 3, 5, 6, 8}, { 0, 1, 4, 8, 2, 3, 5, 6, 7}, { 0, 1, 5, 6, 2, 3, 4, 7, 8}, { 0, 1, 5, 7, 2, 3, 4, 6, 8}, { 0, 1, 5, 8, 2, 3, 4, 6, 7}, { 0, 1, 6, 7, 2, 3, 4, 5, 8}, { 0, 1, 6, 8, 2, 3, 4, 5, 7}, { 0, 1, 7, 8, 2, 3, 4, 5, 6}, { 0, 2, 3, 4, 1, 5, 6, 7, 8}, { 0, 2, 3, 5, 1, 4, 6, 7, 8}, { 0, 2, 3, 6, 1, 4, 5, 7, 8}, { 0, 2, 3, 7, 1, 4, 5, 6, 8}, { 0, 2, 3, 8, 1, 4, 5, 6, 7}, { 0, 2, 4, 5, 1, 3, 6, 7, 8}, { 0, 2, 4, 6, 1, 3, 5, 7, 8}, { 0, 2, 4, 7, 1, 3, 5, 6, 8}, { 0, 2, 4, 8, 1, 3, 5, 6, 7}, { 0, 2, 5, 6, 1, 3, 4, 7, 8}, { 0, 2, 5, 7, 1, 3, 4, 6, 8}, { 0, 2, 5, 8, 1, 3, 4, 6, 7}, { 0, 2, 6, 7, 1, 3, 4, 5, 8}, { 0, 2, 6, 8, 1, 3, 4, 5, 7}, { 0, 2, 7, 8, 1, 3, 4, 5, 6}, { 0, 3, 4, 5, 1, 2, 6, 7, 8}, { 0, 3, 4, 6, 1, 2, 5, 7, 8}, { 0, 3, 4, 7, 1, 2, 5, 6, 8}, { 0, 3, 4, 8, 1, 2, 5, 6, 7}, { 0, 3, 5, 6, 1, 2, 4, 7, 8}, { 0, 3, 5, 7, 1, 2, 4, 6, 8}, { 0, 3, 5, 8, 1, 2, 4, 6, 7}, { 0, 3, 6, 7, 1, 2, 4, 5, 8}, { 0, 3, 6, 8, 1, 2, 4, 5, 7}, { 0, 3, 7, 8, 1, 2, 4, 5, 6}, { 0, 4, 5, 6, 1, 2, 3, 7, 8}, { 0, 4, 5, 7, 1, 2, 3, 6, 8}, { 0, 4, 5, 8, 1, 2, 3, 6, 7}, { 0, 4, 6, 7, 1, 2, 3, 5, 8}, { 0, 4, 6, 8, 1, 2, 3, 5, 7}, { 0, 4, 7, 8, 1, 2, 3, 5, 6}, { 0, 5, 6, 7, 1, 2, 3, 4, 8}, { 0, 5, 6, 8, 1, 2, 3, 4, 7}, { 0, 5, 7, 8, 1, 2, 3, 4, 6}, { 0, 6, 7, 8, 1, 2, 3, 4, 5}, { 1, 2, 3, 4, 0, 5, 6, 7, 8}, { 1, 2, 3, 5, 0, 4, 6, 7, 8}, { 1, 2, 3, 6, 0, 4, 5, 7, 8}, { 1, 2, 3, 7, 0, 4, 5, 6, 8}, { 1, 2, 3, 8, 0, 4, 5, 6, 7}, { 1, 2, 4, 5, 0, 3, 6, 7, 8}, { 1, 2, 4, 6, 0, 3, 5, 7, 8}, { 1, 2, 4, 7, 0, 3, 5, 6, 8}, { 1, 2, 4, 8, 0, 3, 5, 6, 7}, { 1, 2, 5, 6, 0, 3, 4, 7, 8}, { 1, 2, 5, 7, 0, 3, 4, 6, 8}, { 1, 2, 5, 8, 0, 3, 4, 6, 7}, { 1, 2, 6, 7, 0, 3, 4, 5, 8}, { 1, 2, 6, 8, 0, 3, 4, 5, 7}, { 1, 2, 7, 8, 0, 3, 4, 5, 6}, { 1, 3, 4, 5, 0, 2, 6, 7, 8}, { 1, 3, 4, 6, 0, 2, 5, 7, 8}, { 1, 3, 4, 7, 0, 2, 5, 6, 8}, { 1, 3, 4, 8, 0, 2, 5, 6, 7}, { 1, 3, 5, 6, 0, 2, 4, 7, 8}, { 1, 3, 5, 7, 0, 2, 4, 6, 8}, { 1, 3, 5, 8, 0, 2, 4, 6, 7}, { 1, 3, 6, 7, 0, 2, 4, 5, 8}, { 1, 3, 6, 8, 0, 2, 4, 5, 7}, { 1, 3, 7, 8, 0, 2, 4, 5, 6}, { 1, 4, 5, 6, 0, 2, 3, 7, 8}, { 1, 4, 5, 7, 0, 2, 3, 6, 8}, { 1, 4, 5, 8, 0, 2, 3, 6, 7}, { 1, 4, 6, 7, 0, 2, 3, 5, 8}, { 1, 4, 6, 8, 0, 2, 3, 5, 7}, { 1, 4, 7, 8, 0, 2, 3, 5, 6}, { 1, 5, 6, 7, 0, 2, 3, 4, 8}, { 1, 5, 6, 8, 0, 2, 3, 4, 7}, { 1, 5, 7, 8, 0, 2, 3, 4, 6}, { 1, 6, 7, 8, 0, 2, 3, 4, 5}, { 2, 3, 4, 5, 0, 1, 6, 7, 8}, { 2, 3, 4, 6, 0, 1, 5, 7, 8}, { 2, 3, 4, 7, 0, 1, 5, 6, 8}, { 2, 3, 4, 8, 0, 1, 5, 6, 7}, { 2, 3, 5, 6, 0, 1, 4, 7, 8}, { 2, 3, 5, 7, 0, 1, 4, 6, 8}, { 2, 3, 5, 8, 0, 1, 4, 6, 7}, { 2, 3, 6, 7, 0, 1, 4, 5, 8}, { 2, 3, 6, 8, 0, 1, 4, 5, 7}, { 2, 3, 7, 8, 0, 1, 4, 5, 6}, { 2, 4, 5, 6, 0, 1, 3, 7, 8}, { 2, 4, 5, 7, 0, 1, 3, 6, 8}, { 2, 4, 5, 8, 0, 1, 3, 6, 7}, { 2, 4, 6, 7, 0, 1, 3, 5, 8}, { 2, 4, 6, 8, 0, 1, 3, 5, 7}, { 2, 4, 7, 8, 0, 1, 3, 5, 6}, { 2, 5, 6, 7, 0, 1, 3, 4, 8}, { 2, 5, 6, 8, 0, 1, 3, 4, 7}, { 2, 5, 7, 8, 0, 1, 3, 4, 6}, { 2, 6, 7, 8, 0, 1, 3, 4, 5}, { 3, 4, 5, 6, 0, 1, 2, 7, 8}, { 3, 4, 5, 7, 0, 1, 2, 6, 8}, { 3, 4, 5, 8, 0, 1, 2, 6, 7}, { 3, 4, 6, 7, 0, 1, 2, 5, 8}, { 3, 4, 6, 8, 0, 1, 2, 5, 7}, { 3, 4, 7, 8, 0, 1, 2, 5, 6}, { 3, 5, 6, 7, 0, 1, 2, 4, 8}, { 3, 5, 6, 8, 0, 1, 2, 4, 7}, { 3, 5, 7, 8, 0, 1, 2, 4, 6}, { 3, 6, 7, 8, 0, 1, 2, 4, 5}, { 4, 5, 6, 7, 0, 1, 2, 3, 8}, { 4, 5, 6, 8, 0, 1, 2, 3, 7}, { 4, 5, 7, 8, 0, 1, 2, 3, 6}, { 4, 6, 7, 8, 0, 1, 2, 3, 5}, { 5, 6, 7, 8, 0, 1, 2, 3, 4}}, j[54][15] = { // 3 Cell positions Box-Line wise and affected 6 Line + 6 Box Cell positions for Intersection Removals { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,18,19,20}, { 3, 4, 5, 0, 1, 2, 6, 7, 8,12,13,14,21,22,23}, { 6, 7, 8, 0, 1, 2, 3, 4, 5,15,16,17,24,25,26}, { 9,10,11,12,13,14,15,16,17, 0, 1, 2,18,19,20}, {12,13,14, 9,10,11,15,16,17, 3, 4, 5,21,22,23}, {15,16,17, 9,10,11,12,13,14, 6, 7, 8,24,25,26}, {18,19,20,21,22,23,24,25,26, 0, 1, 2, 9,10,11}, {21,22,23,18,19,20,24,25,26, 3, 4, 5,12,13,14}, {24,25,26,18,19,20,21,22,23, 6, 7, 8,15,16,17}, {27,28,29,30,31,32,33,34,35,36,37,38,45,46,47}, {30,31,32,27,28,29,33,34,35,39,40,41,48,49,50}, {33,34,35,27,28,29,30,31,32,42,43,44,51,52,53}, {36,37,38,39,40,41,42,43,44,27,28,29,45,46,47}, {39,40,41,36,37,38,42,43,44,30,31,32,48,49,50}, {42,43,44,36,37,38,39,40,41,33,34,35,51,52,53}, {45,46,47,48,49,50,51,52,53,27,28,29,36,37,38}, {48,49,50,45,46,47,51,52,53,30,31,32,39,40,41}, {51,52,53,45,46,47,48,49,50,33,34,35,42,43,44}, {54,55,56,57,58,59,60,61,62,63,64,65,72,73,74}, {57,58,59,54,55,56,60,61,62,66,67,68,75,76,77}, {60,61,62,54,55,56,57,58,59,69,70,71,78,79,80}, {63,64,65,66,67,68,69,70,71,54,55,56,72,73,74}, {66,67,68,63,64,65,69,70,71,57,58,59,75,76,77}, {69,70,71,63,64,65,66,67,68,60,61,62,78,79,80}, {72,73,74,75,76,77,78,79,80,54,55,56,63,64,65}, {75,76,77,72,73,74,78,79,80,57,58,59,66,67,68}, {78,79,80,72,73,74,75,76,77,60,61,62,69,70,71}, { 0, 9,18,27,36,45,54,63,72, 1, 2,10,11,19,20}, {27,36,45, 0, 9,18,54,63,72,28,29,37,38,46,47}, {54,63,72, 0, 9,18,27,36,45,55,56,64,65,73,74}, { 1,10,19,28,37,46,55,64,73, 0, 2, 9,11,18,20}, {28,37,46, 1,10,19,55,64,73,27,29,36,38,45,47}, {55,64,73, 1,10,19,28,37,46,54,56,63,65,72,74}, { 2,11,20,29,38,47,56,65,74, 0, 1, 9,10,18,19}, {29,38,47, 2,11,20,56,65,74,27,28,36,37,45,46}, {56,65,74, 2,11,20,29,38,47,54,55,63,64,72,73}, { 3,12,21,30,39,48,57,66,75, 4, 5,13,14,22,23}, {30,39,48, 3,12,21,57,66,75,31,32,40,41,49,50}, {57,66,75, 3,12,21,30,39,48,58,59,67,68,76,77}, { 4,13,22,31,40,49,58,67,76, 3, 5,12,14,21,23}, {31,40,49, 4,13,22,58,67,76,30,32,39,41,48,50}, {58,67,76, 4,13,22,31,40,49,57,59,66,68,75,77}, { 5,14,23,32,41,50,59,68,77, 3, 4,12,13,21,22}, {32,41,50, 5,14,23,59,68,77,30,31,39,40,48,49}, {59,68,77, 5,14,23,32,41,50,57,58,66,67,75,76}, { 6,15,24,33,42,51,60,69,78, 7, 8,16,17,25,26}, {33,42,51, 6,15,24,60,69,78,34,35,43,44,52,53}, {60,69,78, 6,15,24,33,42,51,61,62,70,71,79,80}, { 7,16,25,34,43,52,61,70,79, 6, 8,15,17,24,26}, {34,43,52, 7,16,25,61,70,79,33,35,42,44,51,53}, {61,70,79, 7,16,25,34,43,52,60,62,69,71,78,80}, { 8,17,26,35,44,53,62,71,80, 6, 7,15,16,24,25}, {35,44,53, 8,17,26,62,71,80,33,34,42,43,51,52}, {62,71,80, 8,17,26,35,44,53,60,61,69,70,78,79}}; int solve (int p) { int a, x, y = 0, // Represent Naked Single z = 512; // Assign greatest value for first time checking for (a = p; a < q; ++a) // Search Naked/Hidden Single Candidate for each unsolved Cell position { if (B[z] > B[g[r[a]]]) // Check least Candidates for each unsolved Cell position if (B[z = g[r[x = a]]] == 1) goto NHSCF; // Found Naked Single Candidate int K = g[r[a]] & (g[r[a]] ^ (g[w[r[a]][0]] | g[w[r[a]][1]] | g[w[r[a]][2]] | g[w[r[a]][3]] | g[w[r[a]][4]] | g[w[r[a]][5]] | g[w[r[a]][6]] | g[w[r[a]][7]])); // Assign Hidden Candidates for each unsolved Cell position Row wise if (B[K] == 1) // Check Hidden Single Candidate Row wise z = K; // Assign Hidden Single Candidate else { // Assign Hidden Candidates for each unsolved Cell position Column wise K = g[r[a]] & (g[r[a]] ^ (g[w[r[a]][12]] | g[w[r[a]][13]] | g[w[r[a]][14]] | g[w[r[a]][15]] | g[w[r[a]][16]] | g[w[r[a]][17]] | g[w[r[a]][18]] | g[w[r[a]][19]])); if (B[K] == 1) // Check Hidden Single Candidate Column wise z = K; // Assign Hidden Single Candidate else { // Assign Hidden Candidates for each unsolved Cell position Box wise K = g[r[a]] & (g[r[a]] ^ (g[w[r[a]][6]] | g[w[r[a]][7]] | g[w[r[a]][8]] | g[w[r[a]][9]] | g[w[r[a]][10]] | g[w[r[a]][11]] | g[w[r[a]][12]] | g[w[r[a]][13]])); if (B[K] == 1) // Check Hidden Single Candidate Box wise z = K; // Assign Hidden Single Candidate else continue; } } x = a; // Assign Hidden Single Cell position y = 1; // Represent Hidden Single goto NHSCF; } for (; y < 27; ++y) // Search Naked/Hidden Tuples for each Unit { int X = (g[l[y][0]] ? 1 : 0) + (g[l[y][1]] ? 1 : 0) + (g[l[y][2]] ? 1 : 0) + (g[l[y][3]] ? 1 : 0) + (g[l[y][4]] ? 1 : 0) + (g[l[y][5]] ? 1 : 0) + (g[l[y][6]] ? 1 : 0) + (g[l[y][7]] ? 1 : 0) + (g[l[y][8]] ? 1 : 0); // Count unsolved Cell positions if (X < 4) continue; // Skip Unit for less than 4 unsolved Cell positions for (a = 0; a < 36; ++a) // Search Unit 36 pair Cell positions for Naked/Hidden pair { if (!g[l[y][h[a][0]]] || !g[l[y][h[a][1]]]) { // Skip solved Cell positions if (!g[l[y][h[a][0]]]) a += 7 - h[a][0]; continue; } int K[2] = {g[l[y][h[a][0]]] | g[l[y][h[a][1]]], g[l[y][h[a][2]]] | g[l[y][h[a][3]]] | g[l[y][h[a][4]]] | g[l[y][h[a][5]]] | g[l[y][h[a][6]]] | g[l[y][h[a][7]]] | g[l[y][h[a][8]]]}; if (B[K[0]] == 2) // Check Naked pair Candidates in Unit pair Cell positions { if (K[0] & K[1]) // Check Naked pair Candidates in Unit other Cell positions { int k[7] = {g[l[y][h[a][2]]], g[l[y][h[a][3]]], g[l[y][h[a][4]]], g[l[y][h[a][5]]], g[l[y][h[a][6]]], g[l[y][h[a][7]]], g[l[y][h[a][8]]]}; // Backup and remove Naked pair Candidates from Unit other Cell positions g[l[y][h[a][2]]] &= ~K[0]; g[l[y][h[a][3]]] &= ~K[0]; g[l[y][h[a][4]]] &= ~K[0]; g[l[y][h[a][5]]] &= ~K[0]; g[l[y][h[a][6]]] &= ~K[0]; g[l[y][h[a][7]]] &= ~K[0]; g[l[y][h[a][8]]] &= ~K[0]; #ifdef RJ printf ("%d) Found Naked pair Candidates %d at Unit %d Cells %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]]); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore Naked pair Candidates %d at Unit %d Cells %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]]); #endif g[l[y][h[a][2]]] = k[0]; g[l[y][h[a][3]]] = k[1]; g[l[y][h[a][4]]] = k[2]; g[l[y][h[a][5]]] = k[3]; g[l[y][h[a][6]]] = k[4]; g[l[y][h[a][7]]] = k[5]; g[l[y][h[a][8]]] = k[6]; return 0; // Restore Naked pair Candidates to Unit other Cell positions } continue; } K[0] &= K[0] ^ K[1]; // Found more than 2 Candidates in Unit pair Cell positions if (B[K[0]] == 2) // Check Hidden pair Candidates in Unit pair Cell positions { int k[2] = {g[l[y][h[a][0]]], g[l[y][h[a][1]]]}; // Backup and remove other than Hidden pair Candidates from Unit pair Cell positions g[l[y][h[a][0]]] &= K[0]; g[l[y][h[a][1]]] &= K[0]; #ifdef RJ printf ("%d) Found Hidden pair Candidates %d at Unit %d Cells %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]]); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore Hidden pair Candidates %d at Unit %d Cells %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]]); #endif g[l[y][h[a][0]]] = k[0]; g[l[y][h[a][1]]] = k[1]; return 0; // Restore other than Hidden pair Candidates to Unit pair Cell positions } } if (X < 6) continue; // Skip triplets and quads for less than 6 unsolved Cell positions for (; a < 120; ++a) // Search Unit 84 triplet Cell positions { if (!g[l[y][h[a][0]]] || !g[l[y][h[a][1]]] || !g[l[y][h[a][2]]]) { // Skip solved Cell positions if (!g[l[y][h[a][0]]]) { int A[7] = {27,20,14, 9, 5, 2, 0}; a += A[h[a][0]]; } else if (!g[l[y][h[a][1]]]) a += 7 - h[a][1]; continue; } int K[2] = {g[l[y][h[a][0]]] | g[l[y][h[a][1]]] | g[l[y][h[a][2]]], g[l[y][h[a][3]]] | g[l[y][h[a][4]]] | g[l[y][h[a][5]]] | g[l[y][h[a][6]]] | g[l[y][h[a][7]]] | g[l[y][h[a][8]]]}; if (B[K[0]] == 3) // Check Naked triplet Candidates in Unit triplet Cell positions { if (K[0] & K[1]) // Check Naked triplet Candidates in Unit other Cell positions { int k[6] = {g[l[y][h[a][3]]], g[l[y][h[a][4]]], g[l[y][h[a][5]]], g[l[y][h[a][6]]], g[l[y][h[a][7]]], g[l[y][h[a][8]]]}; // Backup and remove Naked triplet Candidates from Unit other Cell positions g[l[y][h[a][3]]] &= ~K[0]; g[l[y][h[a][4]]] &= ~K[0]; g[l[y][h[a][5]]] &= ~K[0]; g[l[y][h[a][6]]] &= ~K[0]; g[l[y][h[a][7]]] &= ~K[0]; g[l[y][h[a][8]]] &= ~K[0]; #ifdef RJ printf ("%d) Found Naked triplet Candidates %d at Unit %d Cells %d %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]], l[y][h[a][2]]); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore Naked triplet Candidates %d at Unit %d Cells %d %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]], l[y][h[a][2]]); #endif g[l[y][h[a][3]]] = k[0]; g[l[y][h[a][4]]] = k[1]; g[l[y][h[a][5]]] = k[2]; g[l[y][h[a][6]]] = k[3]; g[l[y][h[a][7]]] = k[4]; g[l[y][h[a][8]]] = k[5]; return 0; // Restore Naked triplet Candidates to Unit other Cell positions } continue; } K[0] &= K[0] ^ K[1]; // Found more than 3 Candidates in Unit triplet Cell positions if (B[K[0]] == 3) // Check Hidden triplet Candidates in Unit triplet Cell positions { int k[3] = {g[l[y][h[a][0]]], g[l[y][h[a][1]]], g[l[y][h[a][2]]]}; // Backup and remove other than Hidden triplet Candidates from Unit triplet Cell positions g[l[y][h[a][0]]] &= K[0]; g[l[y][h[a][1]]] &= K[0]; g[l[y][h[a][2]]] &= K[0]; #ifdef RJ printf ("%d) Found Hidden triplet Candidates %d at Unit %d Cells %d %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]], l[y][h[a][2]]); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore Hidden triplet Candidates %d at Unit %d Cells %d %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]], l[y][h[a][2]]); #endif g[l[y][h[a][0]]] = k[0]; g[l[y][h[a][1]]] = k[1]; g[l[y][h[a][2]]] = k[2]; return 0; // Restore other than Hidden triplet Candidates to Unit triplet Cell positions } } if (X < 8) continue; // Skip quads for less than 8 unsolved Cell positions for (; a < 246; ++a) // Search Unit 126 quad Cell positions in Unit quad Cell positions { if (!g[l[y][h[a][0]]] || !g[l[y][h[a][1]]] || !g[l[y][h[a][2]]] || !g[l[y][h[a][3]]]) { // Skip solved Cell positions if (!g[l[y][h[a][0]]]) { int A[6] = {55,34,19, 9, 3, 0}; a += A[h[a][0]]; } else if (!g[l[y][h[a][1]]]) { int A[7] = {27,20,14, 9, 5, 2, 0}; a += A[h[a][1]]; } else if (!g[l[y][h[a][2]]]) a += 7 - h[a][2]; continue; } int K[2] = {g[l[y][h[a][0]]] | g[l[y][h[a][1]]] | g[l[y][h[a][2]]] | g[l[y][h[a][3]]], g[l[y][h[a][4]]] | g[l[y][h[a][5]]] | g[l[y][h[a][6]]] | g[l[y][h[a][7]]] | g[l[y][h[a][8]]]}; if (B[K[0]] == 4) // Check Naked quad Candidates in Unit quad Cell positions { if (K[0] & K[1]) // Check Naked quad Candidates in Unit other Cell positions { int k[5] = {g[l[y][h[a][4]]], g[l[y][h[a][5]]], g[l[y][h[a][6]]], g[l[y][h[a][7]]], g[l[y][h[a][8]]]}; // Backup and remove Naked quad Candidates from Unit other Cell positions g[l[y][h[a][4]]] &= ~K[0]; g[l[y][h[a][5]]] &= ~K[0]; g[l[y][h[a][6]]] &= ~K[0]; g[l[y][h[a][7]]] &= ~K[0]; g[l[y][h[a][8]]] &= ~K[0]; #ifdef RJ printf ("%d) Found Naked quad Candidates %d at Unit %d Cells %d %d %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]], l[y][h[a][2]], l[y][h[a][3]]); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore Naked quad Candidates %d at Unit %d Cells %d %d %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]], l[y][h[a][2]], l[y][h[a][3]]); #endif g[l[y][h[a][4]]] = k[0]; g[l[y][h[a][5]]] = k[1]; g[l[y][h[a][6]]] = k[2]; g[l[y][h[a][7]]] = k[3]; g[l[y][h[a][8]]] = k[4]; return 0; // Restore Naked quad Candidates to Unit other Cell positions } continue; } K[0] &= K[0] ^ K[1]; // Found more than 4 Candidates in Unit quad Cell positions if (B[K[0]] == 4) // Check Hidden quad Candidates in Unit quad Cell positions { int k[4] = {g[l[y][h[a][0]]], g[l[y][h[a][1]]], g[l[y][h[a][2]]], g[l[y][h[a][3]]]}; // Backup and remove other than Hidden quad Candidates from Unit quad Cell positions g[l[y][h[a][0]]] &= K[0]; g[l[y][h[a][1]]] &= K[0]; g[l[y][h[a][2]]] &= K[0]; g[l[y][h[a][3]]] &= K[0]; #ifdef RJ printf ("%d) Found Hidden quad Candidates %d at Unit %d Cells %d %d %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]], l[y][h[a][2]], l[y][h[a][3]]); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore Hidden quad Candidates %d at Unit %d Cells %d %d %d %d\n", a, b[K[0]], y, l[y][h[a][0]], l[y][h[a][1]], l[y][h[a][2]], l[y][h[a][3]]); #endif g[l[y][h[a][0]]] = k[0]; g[l[y][h[a][1]]] = k[1]; g[l[y][h[a][2]]] = k[2]; g[l[y][h[a][3]]] = k[3]; return 0; // Restore other than Hidden quad Candidates to Unit quad Cell positions } } } for (y = 0; y < 54; ++y) // Search 54 Box-Line Cell positions for Intersection Removal Candidate for (a = 0; a < 9; ++a) // Search Intersection Removal Candidate for each Box-Line Cell positions if ((g[j[y][0]] >> a) & 1 || (g[j[y][1]] >> a) & 1 || (g[j[y][2]] >> a) & 1) { // Found Intersection Removal Candidate in Box-Line Cell positions if ((g[j[y][3]] >> a) & 1 || (g[j[y][4]] >> a) & 1 || (g[j[y][5]] >> a) & 1 || (g[j[y][6]] >> a) & 1 || (g[j[y][7]] >> a) & 1 || (g[j[y][8]] >> a) & 1) { // Found Intersection Removal Candidate in Line other Cell positions if (!((g[j[y][9]] >> a) & 1 || (g[j[y][10]] >> a) & 1 || (g[j[y][11]] >> a) & 1 || (g[j[y][12]] >> a) & 1 || (g[j[y][13]] >> a) & 1 || (g[j[y][14]] >> a) & 1)) { // Not found Intersection Removal Candidate in Box other Cell positions int k = (g[j[y][3]] >> a) & 1 | ((g[j[y][4]] >> a) & 1) << 1 | ((g[j[y][5]] >> a) & 1) << 2 | ((g[j[y][6]] >> a) & 1) << 3 | ((g[j[y][7]] >> a) & 1) << 4 | ((g[j[y][8]] >> a) & 1) << 5; // Backup and remove Intersection Removal Candidate in Line other Cell positions g[j[y][3]] &= ~(1 << a); g[j[y][4]] &= ~(1 << a); g[j[y][5]] &= ~(1 << a); g[j[y][6]] &= ~(1 << a); g[j[y][7]] &= ~(1 << a); g[j[y][8]] &= ~(1 << a); #ifdef RJ printf ("%d) Found Pointing and Claiming Intersection Removal Candidate %d at Cells %d %d %d\n", y, a + 1, j[y][0], j[y][1], j[y][2]); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore Pointing and Claiming Intersection Removal Candidate %d at Cells %d %d %d\n", y, a + 1, j[y][0], j[y][1], j[y][2]); #endif g[j[y][3]] |= (k & 1) << a; g[j[y][4]] |= ((k >> 1) & 1) << a; g[j[y][5]] |= ((k >> 2) & 1) << a; g[j[y][6]] |= ((k >> 3) & 1) << a; g[j[y][7]] |= ((k >> 4) & 1) << a; g[j[y][8]] |= ((k >> 5) & 1) << a; return 0; // Restore Intersection Removal Candidate in Line other Cell positions } continue; } // Not found Intersection Removal Candidate in Line other Cell positions if ((g[j[y][9]] >> a) & 1 || (g[j[y][10]] >> a) & 1 || (g[j[y][11]] >> a) & 1 || (g[j[y][12]] >> a) & 1 || (g[j[y][13]] >> a) & 1 || (g[j[y][14]] >> a) & 1) { // Found Intersection Removal Candidate in Box other Cell positions int k = (g[j[y][9]] >> a) & 1 | ((g[j[y][10]] >> a) & 1) << 1 | ((g[j[y][11]] >> a) & 1) << 2 | ((g[j[y][12]] >> a) & 1) << 3 | ((g[j[y][13]] >> a) & 1) << 4 | ((g[j[y][14]] >> a) & 1) << 5; // Backup and remove Intersection Removal Candidate in Box other Cell positions g[j[y][9]] &= ~(1 << a); g[j[y][10]] &= ~(1 << a); g[j[y][11]] &= ~(1 << a); g[j[y][12]] &= ~(1 << a); g[j[y][13]] &= ~(1 << a); g[j[y][14]] &= ~(1 << a); #ifdef RJ printf ("%d) Found Box-Line Reduction Intersection Removal Candidate %d at Cells %d %d %d\n", y, a + 1, j[y][0], j[y][1], j[y][2]); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore Box-Line Reduction Intersection Removal Candidate %d at Cells %d %d %d\n", y, a + 1, j[y][0], j[y][1], j[y][2]); #endif g[j[y][9]] |= (k & 1) << a; g[j[y][10]] |= ((k >> 1) & 1) << a; g[j[y][11]] |= ((k >> 2) & 1) << a; g[j[y][12]] |= ((k >> 3) & 1) << a; g[j[y][13]] |= ((k >> 4) & 1) << a; g[j[y][14]] |= ((k >> 5) & 1) << a; return 0; // Restore Intersection Removal Candidate in Box other Cell positions } } for (y = 0; y < 18; ++y) // Search Basic Fishes for each Line { int k[10], // Backup Line Cell positions and Basic Fish Candidate Y = y < 9 ? 0 : 9; // Assign either Row or Column wise for (k[9] = y - Y, a = Y; a < Y + 9; ++a) k[a - Y] = (g[l[a][0]] >> k[9]) & 1 | ((g[l[a][1]] >> k[9]) & 1) << 1 | ((g[l[a][2]] >> k[9]) & 1) << 2 | ((g[l[a][3]] >> k[9]) & 1) << 3 | ((g[l[a][4]] >> k[9]) & 1) << 4 | ((g[l[a][5]] >> k[9]) & 1) << 5 | ((g[l[a][6]] >> k[9]) & 1) << 6 | ((g[l[a][7]] >> k[9]) & 1) << 7 | ((g[l[a][8]] >> k[9]) & 1) << 8; for (a = 0; a < 36; ++a) // Search X-Wing Candidate in Line 36 pair Cell positions { int A = k[h[a][0]], K[2], X = -1; if (B[A] != 2 || A != k[h[a][1]]) { // Skip for X-Wing Candidate not found in Lines pair Cell positions if (B[A] != 2) a += 7 - h[a][0]; continue; } for (int L = A, Z = -1; L; L &= L - 1) { K[++Z] = b[L & -L] - 1; if (!((k[h[a][2]] >> K[Z]) & 1 || (k[h[a][3]] >> K[Z]) & 1 || (k[h[a][4]] >> K[Z]) & 1 || (k[h[a][5]] >> K[Z]) & 1 || (k[h[a][6]] >> K[Z]) & 1 || (k[h[a][7]] >> K[Z]) & 1 || (k[h[a][8]] >> K[Z]) & 1)) continue; // Skip opposite Line for X-Wing Candidate not found in opposite Line other Cell positions X = K[Z] - Y + 9; // Remove X-Wing Candidate from opposite Line other Cell positions g[l[X][h[a][2]]] &= ~(1 << k[9]); g[l[X][h[a][3]]] &= ~(1 << k[9]); g[l[X][h[a][4]]] &= ~(1 << k[9]); g[l[X][h[a][5]]] &= ~(1 << k[9]); g[l[X][h[a][6]]] &= ~(1 << k[9]); g[l[X][h[a][7]]] &= ~(1 << k[9]); g[l[X][h[a][8]]] &= ~(1 << k[9]); } if (X < 0) continue; // Skip for X-Wing Candidate not found in opposite Lines other Cell positions #ifdef RJ printf ("%d) Found %s X-Wing for Candidate %d at r%d%dc%d%d\n", a, Y ? "Column wise" : "Row wise", k[9] + 1, (Y ? K[0] : h[a][0]) + 1, (Y ? K[1] : h[a][1]) + 1, (Y ? h[a][0] : K[0]) + 1, (Y ? h[a][1] : K[1]) + 1); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore %s X-Wing for Candidate %d at r%d%dc%d%d\n", a, Y ? "Column wise" : "Row wise", k[9] + 1, (Y ? K[0] : h[a][0]) + 1, (Y ? K[1] : h[a][1]) + 1, (Y ? h[a][0] : K[0]) + 1, (Y ? h[a][1] : K[1]) + 1); #endif for (int Z = 0; Z < 2; ++Z) { // Restore X-Wing Candidate to opposite Lines other Cell positions X = K[Z] - Y + 9; g[l[X][h[a][2]]] |= ((k[h[a][2]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][3]]] |= ((k[h[a][3]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][4]]] |= ((k[h[a][4]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][5]]] |= ((k[h[a][5]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][6]]] |= ((k[h[a][6]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][7]]] |= ((k[h[a][7]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][8]]] |= ((k[h[a][8]] >> K[Z]) & 1) << k[9]; } return 0; } for (; a < 120; ++a) // Search Sword Fish Candidate in Line 84 triplet Cell positions { int A = k[h[a][0]] | k[h[a][1]] | k[h[a][2]], K[3], X = -1; if (!k[h[a][0]] || !k[h[a][1]] || !k[h[a][2]] || B[A] != 3) { // Skip for either solved Cell positions or Sord Fish Candidate not found in Lines triplet Cell positions if (!k[h[a][0]] || B[k[h[a][0]]] > 3) { int A[7] = {27,20,14, 9, 5, 2, 0}; a += A[h[a][0]]; } else if (!k[h[a][1]] || B[k[h[a][1]]] > 3) a += 7 - h[a][1]; continue; } for (int L = A, Z = -1; L; L &= L - 1) { K[++Z] = b[L & -L] - 1; if (!((k[h[a][3]] >> K[Z]) & 1 || (k[h[a][4]] >> K[Z]) & 1 || (k[h[a][5]] >> K[Z]) & 1 || (k[h[a][6]] >> K[Z]) & 1 || (k[h[a][7]] >> K[Z]) & 1 || (k[h[a][8]] >> K[Z]) & 1)) continue; // Skip opposite Line for Sword Fish Candidate not found in opposite Line other Cell positions X = K[Z] - Y + 9; // Remove Sword Fish Candidate from opposite Line other Cell positions g[l[X][h[a][3]]] &= ~(1 << k[9]); g[l[X][h[a][4]]] &= ~(1 << k[9]); g[l[X][h[a][5]]] &= ~(1 << k[9]); g[l[X][h[a][6]]] &= ~(1 << k[9]); g[l[X][h[a][7]]] &= ~(1 << k[9]); g[l[X][h[a][8]]] &= ~(1 << k[9]); } if (X < 0) continue; // Skip for Sword Fish Candidate not found in opposite Lines other Cell positions #ifdef RJ printf ("%d) Found %s Sword Fish for Candidate %d at r%d%d%dc%d%d%d\n", a, Y ? "Column wise" : "Row wise", k[9] + 1, (Y ? K[0] : h[a][0]) + 1, (Y ? K[1] : h[a][1]) + 1, (Y ? K[2] : h[a][2]) + 1, (Y ? h[a][0] : K[0]) + 1, (Y ? h[a][1] : K[1]) + 1, (Y ? h[a][2] : K[2]) + 1); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore %s Sword Fish for Candidate %d at r%d%d%dc%d%d%d\n", a, Y ? "Column wise" : "Row wise", k[9] + 1, (Y ? K[0] : h[a][0]) + 1, (Y ? K[1] : h[a][1]) + 1, (Y ? K[2] : h[a][2]) + 1, (Y ? h[a][0] : K[0]) + 1, (Y ? h[a][1] : K[1]) + 1, (Y ? h[a][2] : K[2]) + 1); #endif for (int Z = 0; Z < 3; ++Z) { // Restore Sword Fish Candidate to opposite Lines other Cell positions X = K[Z] - Y + 9; g[l[X][h[a][3]]] |= ((k[h[a][3]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][4]]] |= ((k[h[a][4]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][5]]] |= ((k[h[a][5]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][6]]] |= ((k[h[a][6]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][7]]] |= ((k[h[a][7]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][8]]] |= ((k[h[a][8]] >> K[Z]) & 1) << k[9]; } return 0; } for (; a < 246; ++a) // Search Jelly Fish Candidate in Line 126 quad Cell positions { int A = k[h[a][0]] | k[h[a][1]] | k[h[a][2]] | k[h[a][3]], K[4], X = -1; if (!k[h[a][0]] || !k[h[a][1]] || !k[h[a][2]] || !k[h[a][3]] || B[A] != 4) { // Skip for either solved Cell positions or Jelly Fish Candidate not found in Line quad Cell positions if (!k[h[a][0]] || B[k[h[a][0]]] > 4) { int A[6] = {55,34,19, 9, 3, 0}; a += A[h[a][0]]; } else if (!k[h[a][1]] || B[k[h[a][1]]] > 4) { int A[7] = {27,20,14, 9, 5, 2, 0}; a += A[h[a][1]]; } else if (!k[h[a][2]] || B[k[h[a][2]]] > 4) a += 7 - h[a][2]; continue; } for (int L = A, Z = -1; L; L &= L - 1) { K[++Z] = b[L & -L] - 1; if (!((k[h[a][4]] >> K[Z]) & 1 || (k[h[a][5]] >> K[Z]) & 1 || (k[h[a][6]] >> K[Z]) & 1 || (k[h[a][7]] >> K[Z]) & 1 || (k[h[a][8]] >> K[Z]) & 1)) continue; // Skip for Jelly Fish Candidate not found in opposite Line other Cell positions X = K[Z] - Y + 9; // Remove Jelly Fish Candidate from opposite Line other Cell positions g[l[X][h[a][4]]] &= ~(1 << k[9]); g[l[X][h[a][5]]] &= ~(1 << k[9]); g[l[X][h[a][6]]] &= ~(1 << k[9]); g[l[X][h[a][7]]] &= ~(1 << k[9]); g[l[X][h[a][8]]] &= ~(1 << k[9]); } if (X < 0) continue; // Skip for Jelly Fish Candidate not found in opposite Lines other Cell positions #ifdef RJ printf ("%d) Found %s Jelly Fish for Candidate %d at r%d%d%d%dc%d%d%d%d\n", a, Y ? "Column wise" : "Row wise", k[9] + 1, (Y ? K[0] : h[a][0]) + 1, (Y ? K[1] : h[a][1]) + 1, (Y ? K[2] : h[a][2]) + 1, (Y ? K[3] : h[a][3]) + 1, (Y ? h[a][0] : K[0]) + 1, (Y ? h[a][1] : K[1]) + 1, (Y ? h[a][2] : K[2]) + 1, (Y ? h[a][3] : K[3]) + 1); #endif if (solve (p)) return 1; #ifdef RJ printf ("%d) Restore %s Jelly Fish for Candidate %d at r%d%d%d%dc%d%d%d%d\n", a, Y ? "Column wise" : "Row wise", k[9] + 1, (Y ? K[0] : h[a][0]) + 1, (Y ? K[1] : h[a][1]) + 1, (Y ? K[2] : h[a][2]) + 1, (Y ? K[3] : h[a][3]) + 1, (Y ? h[a][0] : K[0]) + 1, (Y ? h[a][1] : K[1]) + 1, (Y ? h[a][2] : K[2]) + 1, (Y ? h[a][3] : K[3]) + 1); #endif for (int Z = 0; Z < 4; ++Z) { // Restore Jelly Fish Candidate to opposite Lines other Cell positions X = K[Z] - Y + 9; g[l[X][h[a][4]]] |= ((k[h[a][4]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][5]]] |= ((k[h[a][5]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][6]]] |= ((k[h[a][6]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][7]]] |= ((k[h[a][7]] >> K[Z]) & 1) << k[9]; g[l[X][h[a][8]]] |= ((k[h[a][8]] >> K[Z]) & 1) << k[9]; } return 0; } } y = 2; // Represent Guess NHSCF: if (x > p) // Check current Cell position for sorting and eliminating { a = r[p]; r[p] = r[x]; r[x] = a; } int K = g[r[p]]; // Backup current Cell position Candidates for (g[r[p]] = 0; s[r[p]] = b[z & -z]; z &= z - 1) { // Remove current Cell position Candidates and solve current Cell position Candidate wise int k = 0; for (++n[y], a = 0; a < 20; ++a) if (g[w[r[p]][a]] & (1 << (s[r[p]] - 1))) { k |= 1 << a; // Backup affected 20 Cell positions current Candidate g[w[r[p]][a]] &= ~(1 << (s[r[p]] - 1)); } // Remove current Candidate from affected 20 Cell positions #ifdef RJ printf ("%d) Apply %s Candidate %d from Candidates %d at Cell %d\n", p, y ? (y > 1 ? "Trial and Error" : "Hidden Single") : "Naked Single", s[r[p]], b[K], r[p]); #endif if (a > 19 && (p + 1 >= q || solve (p + 1))) return 1; // If either all Cell positions solved or recursive solve for next unsolved Cell position #ifdef RJ printf ("%d) Restore %s Candidate %d from Candidates %d at Cell %d\n", p, y ? (y > 1 ? "Trial and Error" : "Hidden Single") : "Naked Single", s[r[p]], b[K], r[p]); #endif while (a > 0) // Restore current Candidate to affected 20 Cell positions g[w[r[p]][--a]] |= ((k >> a) & 1) << (s[r[p]] - 1); } g[r[p]] = K; // Restore Candidates to current Cell position return 0; } int check (int p, int q) { for (int a = 0; a < 20; ++a) if (s[w[p][a]] == q) // Check duplicate Candidate in affected 20 clue Cell positions return 0; return 1; } int invalid (void) { for (int p = 0; p < 81; ++p) if (!s[p]) // Check unsolved Cell position { for (int a = 0; a < 9; ++a) g[p] |= check (p, a + 1) << a; // Check constraint and assign Candidate for unsolved Cell position if (!g[p]) // Check no Candidate assigned return 1; r[q++] = p; // Assign unsolved Cell position for sorting and eliminating } else if (!check (p, s[p])) // Check constraint for clue Cell position return 1; return 0; } int main (void) { int a = -1, m, i = 0, t = 0, u = 0, v = 0, y = 0; float c, d = 0, e = 0, f = 0, k = 0; FILE *o = fopen ("sudoku.txt", "r"); if (o == NULL) printf ("Unable to open sudoku.txt file for read !!\n"); else do { if ((m = fgetc (o)) != 10 && m != EOF && a < 80) s[++a] = m >= '1' && m <= '9' ? m - '0' : 0; else // Assign clue Cell positions if (m == 10 || m == EOF) { #ifdef RJ printf ("\n"); #endif while (a < 80) // Clear remaining unsolved Cell positions s[++a] = 0; q = n[0] = n[1] = n[2] = 0; c = clock (); if (invalid ()) { c = (clock () - c) / CLOCKS_PER_SEC * 1000; d += c; printf ("%ld) Error: Invalid Sudoku! # I%ld", ++t, ++i); } else if (!q) { c = (clock () - c) / CLOCKS_PER_SEC * 1000; k += c; printf ("%ld) Valid Sudoku # V%ld", ++t, ++y); } else if (solve (0)) { c = (clock () - c) / CLOCKS_PER_SEC * 1000; e += c; printf ("%ld) ", ++t); for (a = 0; a < 81; ++a) printf ("%c", s[a] + '0'); printf (" # S%ld", ++v); } else { c = (clock () - c) / CLOCKS_PER_SEC * 1000; f += c; printf ("%ld) Error: Unsolvable Sudoku! # U%ld", ++t, ++u); } printf (" # N%ld # H%ld # G%ld # %f\n", n[0], n[1], n[2], c); a = -1; } #ifdef RJ if (m != EOF) printf ("%c", m); #endif } while (m != EOF); printf ("=======================================\n"); printf ("Total Sudoku puzzle read : %ld\n", t); printf ("Total time for all puzzles : %f\n", d + e + f + y); printf ("Average time per puzzle : %f\n", t ? (d + e + f + y) / t : 0); printf ("Number of valid puzzles : %ld\n", y); printf ("Time for valid puzzles : %f\n", k); printf ("Average time per valid : %f\n", y ? k / y : 0); printf ("Number of invalid puzzles : %ld\n", i); printf ("Time for invalid puzzles : %f\n", d); printf ("Average time per invalid : %f\n", i ? d / i : 0); printf ("Number of solved puzzles : %ld\n", v); printf ("Time for solved puzzles : %f\n", e); printf ("Average time per solved : %f\n", v ? e / v : 0); printf ("Number of unsolved puzzle : %ld\n", u); printf ("Time for unsolved puzzles : %f\n", f); printf ("Average time per unsolved : %f\n", u ? f / u : 0); if (fclose (o) == EOF) printf ("Unable to close sudoku.txt file !!"); }