#include <iostream> #include <set> using namespace std; const int ModBy = 1000000000 + 7; const char FREE = '.'; const char TILE = '#'; const char VISITED = 'V'; const int MaxBoardSize = 3000; char Board[MaxBoardSize][MaxBoardSize]; int BoardSize; int NumPlayers; int NumFields; set< set<int> > Solutions; unsigned long long SolutionsCount = 0; int getFieldIdx(int row, int col) { return BoardSize * row + col; } void setFieldValue(int idx, char value) { int row = idx / BoardSize; int col = idx % BoardSize; Board[row][col] = value; } void AlgorithmStep(int LeadFieldNumber, set<int> AvailableFields, int Steps, set<int> Solution) { int row = LeadFieldNumber / BoardSize; int col = LeadFieldNumber % BoardSize; setFieldValue(LeadFieldNumber, TILE); // We placed a tile - we made a step ++Steps; Solution.insert(LeadFieldNumber); if (Steps == NumPlayers) { // All players made their steps // Save solution Solutions.insert(Solution); setFieldValue(LeadFieldNumber, FREE); return; } if (row - 1 >= 0 && Board[row - 1][col] == FREE) { AvailableFields.insert(getFieldIdx(row - 1, col)); } if (col - 1 >= 0 && Board[row][col - 1] == FREE) { AvailableFields.insert(getFieldIdx(row, col - 1)); } if (row + 1 < BoardSize && Board[row + 1][col] == FREE) { AvailableFields.insert(getFieldIdx(row + 1, col)); } if (col + 1 < BoardSize && Board[row][col + 1] == FREE) { AvailableFields.insert(getFieldIdx(row, col + 1)); } while (!AvailableFields.empty()) { auto it = AvailableFields.begin(); int NextFieldNumber = *it; AvailableFields.erase(it); AlgorithmStep(NextFieldNumber, AvailableFields, Steps, Solution); } setFieldValue(LeadFieldNumber, FREE); } int main() { scanf("%d", &BoardSize); scanf("%d", &NumPlayers); NumFields = BoardSize * BoardSize; char GridItem; set<int> InitialAvailableFields; int previousCol; int previousRow; for (int row = 0; row < BoardSize; ++row) { for (int col = 0; col < BoardSize; ++col) { scanf(" %c", &GridItem); previousCol = col - 1; previousRow = row - 1; if (GridItem == '#') { Board[row][col] = TILE; if (previousCol >= 0 && Board[row][previousCol] == FREE) { InitialAvailableFields.insert(getFieldIdx(row, previousCol)); } else if (previousRow >= 0 && Board[previousRow][col] == FREE) { InitialAvailableFields.insert(getFieldIdx(previousRow, col)); } } else { Board[row][col] = FREE; if ((previousCol >= 0 && Board[row][previousCol] == TILE) || (previousRow >= 0 && Board[previousRow][col] == TILE)) { InitialAvailableFields.insert(getFieldIdx(row, col)); } } } } set<int> emptySolution; while (!InitialAvailableFields.empty()) { auto it = InitialAvailableFields.begin(); int LeadFieldNumber = *it; InitialAvailableFields.erase(it); // DO work AlgorithmStep(LeadFieldNumber, InitialAvailableFields, 0, emptySolution); setFieldValue(LeadFieldNumber, VISITED); unsigned long long SolutionsInStep = Solutions.size(); SolutionsCount = (SolutionsCount + SolutionsInStep % ModBy) % ModBy; Solutions.clear(); } cout << SolutionsCount << endl; return 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 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 | #include <iostream> #include <set> using namespace std; const int ModBy = 1000000000 + 7; const char FREE = '.'; const char TILE = '#'; const char VISITED = 'V'; const int MaxBoardSize = 3000; char Board[MaxBoardSize][MaxBoardSize]; int BoardSize; int NumPlayers; int NumFields; set< set<int> > Solutions; unsigned long long SolutionsCount = 0; int getFieldIdx(int row, int col) { return BoardSize * row + col; } void setFieldValue(int idx, char value) { int row = idx / BoardSize; int col = idx % BoardSize; Board[row][col] = value; } void AlgorithmStep(int LeadFieldNumber, set<int> AvailableFields, int Steps, set<int> Solution) { int row = LeadFieldNumber / BoardSize; int col = LeadFieldNumber % BoardSize; setFieldValue(LeadFieldNumber, TILE); // We placed a tile - we made a step ++Steps; Solution.insert(LeadFieldNumber); if (Steps == NumPlayers) { // All players made their steps // Save solution Solutions.insert(Solution); setFieldValue(LeadFieldNumber, FREE); return; } if (row - 1 >= 0 && Board[row - 1][col] == FREE) { AvailableFields.insert(getFieldIdx(row - 1, col)); } if (col - 1 >= 0 && Board[row][col - 1] == FREE) { AvailableFields.insert(getFieldIdx(row, col - 1)); } if (row + 1 < BoardSize && Board[row + 1][col] == FREE) { AvailableFields.insert(getFieldIdx(row + 1, col)); } if (col + 1 < BoardSize && Board[row][col + 1] == FREE) { AvailableFields.insert(getFieldIdx(row, col + 1)); } while (!AvailableFields.empty()) { auto it = AvailableFields.begin(); int NextFieldNumber = *it; AvailableFields.erase(it); AlgorithmStep(NextFieldNumber, AvailableFields, Steps, Solution); } setFieldValue(LeadFieldNumber, FREE); } int main() { scanf("%d", &BoardSize); scanf("%d", &NumPlayers); NumFields = BoardSize * BoardSize; char GridItem; set<int> InitialAvailableFields; int previousCol; int previousRow; for (int row = 0; row < BoardSize; ++row) { for (int col = 0; col < BoardSize; ++col) { scanf(" %c", &GridItem); previousCol = col - 1; previousRow = row - 1; if (GridItem == '#') { Board[row][col] = TILE; if (previousCol >= 0 && Board[row][previousCol] == FREE) { InitialAvailableFields.insert(getFieldIdx(row, previousCol)); } else if (previousRow >= 0 && Board[previousRow][col] == FREE) { InitialAvailableFields.insert(getFieldIdx(previousRow, col)); } } else { Board[row][col] = FREE; if ((previousCol >= 0 && Board[row][previousCol] == TILE) || (previousRow >= 0 && Board[previousRow][col] == TILE)) { InitialAvailableFields.insert(getFieldIdx(row, col)); } } } } set<int> emptySolution; while (!InitialAvailableFields.empty()) { auto it = InitialAvailableFields.begin(); int LeadFieldNumber = *it; InitialAvailableFields.erase(it); // DO work AlgorithmStep(LeadFieldNumber, InitialAvailableFields, 0, emptySolution); setFieldValue(LeadFieldNumber, VISITED); unsigned long long SolutionsInStep = Solutions.size(); SolutionsCount = (SolutionsCount + SolutionsInStep % ModBy) % ModBy; Solutions.clear(); } cout << SolutionsCount << endl; return 0; } |