A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
Let's break this down into a clear plan and then implement it. Plan: 1. Represent 8x8 matrix using an unsigned long (64 bits) 2. Create helper functions: - is_unholy: Checks if a matrix has no isolated 1s - count_unholy: Dynamic programming function to count unholy matrices 3. Main dynamic programming approach: - State: Previous two rows and current height - For each state, try all possible next two rows - Check if new configuration maintains "unholiness" - Use memoization to store results Here's the implementation:
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 | #include <stdio.h> #include <string.h> // DP table size: 2^16 states (for two rows) * 4 heights unsigned long long dp[65536][4]; int calculated[65536][4]; // Check if a specific position has an isolated 1 int is_isolated(unsigned long matrix, int row, int col) { if ((matrix & (1UL << (row * 8 + col))) == 0) return 0; // Check all four directions if (row > 0 && (matrix & (1UL << ((row-1) * 8 + col)))) return 0; if (row < 7 && (matrix & (1UL << ((row+1) * 8 + col)))) return 0; if (col > 0 && (matrix & (1UL << (row * 8 + col-1)))) return 0; if (col < 7 && (matrix & (1UL << (row * 8 + col+1)))) return 0; return 1; } // Check if matrix is unholy (no isolated 1s) int is_unholy(unsigned long matrix) { for(int i = 0; i < 8; i++) for(int j = 0; j < 8; j++) if (is_isolated(matrix, i, j)) return 0; return 1; } // Check if current configuration is valid int is_valid_config(unsigned prev_rows, unsigned new_rows, int height) { unsigned long matrix = 0; // Construct partial matrix matrix |= ((unsigned long)prev_rows) << (8 * (height-2)); matrix |= ((unsigned long)new_rows) << (8 * height); // Check only relevant rows for isolation for(int i = height-1; i <= height; i++) for(int j = 0; j < 8; j++) if (is_isolated(matrix, i, j)) return 0; return 1; } // Dynamic programming function unsigned long long count_unholy(unsigned prev_rows, int height) { if (height == 4) return 1; // Reached full height if (calculated[prev_rows][height]) return dp[prev_rows][height]; calculated[prev_rows][height] = 1; unsigned long long result = 0; // Try all possible next two rows for(unsigned new_rows = 0; new_rows < (1<<16); new_rows++) { if (is_valid_config(prev_rows, new_rows, height)) { result += count_unholy(new_rows, height + 1); } } dp[prev_rows][height] = result; return result; } int main() { // Initialize memoization tables memset(calculated, 0, sizeof(calculated)); memset(dp, 0, sizeof(dp)); unsigned long long total = 0; // Try all possible first two rows for(unsigned first_rows = 0; first_rows < (1<<16); first_rows++) { total += count_unholy(first_rows, 1); } printf("Total number of unholy 8x8 matrices: %llu\n", total); return 0; } |
I extracted the following code from that output:
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 | #include <stdio.h> #include <string.h> // DP table size: 2^16 states (for two rows) * 4 heights unsigned long long dp[65536][4]; int calculated[65536][4]; // Check if a specific position has an isolated 1 int is_isolated(unsigned long matrix, int row, int col) { if ((matrix & (1UL << (row * 8 + col))) == 0) return 0; // Check all four directions if (row > 0 && (matrix & (1UL << ((row-1) * 8 + col)))) return 0; if (row < 7 && (matrix & (1UL << ((row+1) * 8 + col)))) return 0; if (col > 0 && (matrix & (1UL << (row * 8 + col-1)))) return 0; if (col < 7 && (matrix & (1UL << (row * 8 + col+1)))) return 0; return 1; } // Check if matrix is unholy (no isolated 1s) int is_unholy(unsigned long matrix) { for(int i = 0; i < 8; i++) for(int j = 0; j < 8; j++) if (is_isolated(matrix, i, j)) return 0; return 1; } // Check if current configuration is valid int is_valid_config(unsigned prev_rows, unsigned new_rows, int height) { unsigned long matrix = 0; // Construct partial matrix matrix |= ((unsigned long)prev_rows) << (8 * (height-2)); matrix |= ((unsigned long)new_rows) << (8 * height); // Check only relevant rows for isolation for(int i = height-1; i <= height; i++) for(int j = 0; j < 8; j++) if (is_isolated(matrix, i, j)) return 0; return 1; } // Dynamic programming function unsigned long long count_unholy(unsigned prev_rows, int height) { if (height == 4) return 1; // Reached full height if (calculated[prev_rows][height]) return dp[prev_rows][height]; calculated[prev_rows][height] = 1; unsigned long long result = 0; // Try all possible next two rows for(unsigned new_rows = 0; new_rows < (1<<16); new_rows++) { if (is_valid_config(prev_rows, new_rows, height)) { result += count_unholy(new_rows, height + 1); } } dp[prev_rows][height] = result; return result; } int main() { // Initialize memoization tables memset(calculated, 0, sizeof(calculated)); memset(dp, 0, sizeof(dp)); unsigned long long total = 0; // Try all possible first two rows for(unsigned first_rows = 0; first_rows < (1<<16); first_rows++) { total += count_unholy(first_rows, 1); } printf("Total number of unholy 8x8 matrices: %llu\n", total); return 0; } |
Running the following program:
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 | #include <stdio.h> #include <string.h> // DP table size: 2^16 states (for two rows) * 4 heights unsigned long long dp[65536][4]; int calculated[65536][4]; // Check if a specific position has an isolated 1 int is_isolated(unsigned long matrix, int row, int col) { if ((matrix & (1UL << (row * 8 + col))) == 0) return 0; // Check all four directions if (row > 0 && (matrix & (1UL << ((row-1) * 8 + col)))) return 0; if (row < 7 && (matrix & (1UL << ((row+1) * 8 + col)))) return 0; if (col > 0 && (matrix & (1UL << (row * 8 + col-1)))) return 0; if (col < 7 && (matrix & (1UL << (row * 8 + col+1)))) return 0; return 1; } // Check if matrix is unholy (no isolated 1s) int is_unholy(unsigned long matrix) { for(int i = 0; i < 8; i++) for(int j = 0; j < 8; j++) if (is_isolated(matrix, i, j)) return 0; return 1; } // Check if current configuration is valid int is_valid_config(unsigned prev_rows, unsigned new_rows, int height) { unsigned long matrix = 0; // Construct partial matrix matrix |= ((unsigned long)prev_rows) << (8 * (height-2)); matrix |= ((unsigned long)new_rows) << (8 * height); // Check only relevant rows for isolation for(int i = height-1; i <= height; i++) for(int j = 0; j < 8; j++) if (is_isolated(matrix, i, j)) return 0; return 1; } // Dynamic programming function unsigned long long count_unholy(unsigned prev_rows, int height) { if (height == 4) return 1; // Reached full height if (calculated[prev_rows][height]) return dp[prev_rows][height]; calculated[prev_rows][height] = 1; unsigned long long result = 0; // Try all possible next two rows for(unsigned new_rows = 0; new_rows < (1<<16); new_rows++) { if (is_valid_config(prev_rows, new_rows, height)) { result += count_unholy(new_rows, height + 1); } } dp[prev_rows][height] = result; return result; } int main() { // Initialize memoization tables memset(calculated, 0, sizeof(calculated)); memset(dp, 0, sizeof(dp)); unsigned long long total = 0; // Try all possible first two rows for(unsigned first_rows = 0; first_rows < (1<<16); first_rows++) { total += count_unholy(first_rows, 1); } printf("Total number of unholy 8x8 matrices: %llu\n", total); return 0; } |
Timeout: function took too long to complete
Testing if the previous output contains the string 1121231537486377866
: False
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
Let's break this down into a structured plan and then implement it. Plan: 1. Represent the 8x8 matrix using an unsigned long (64 bits) 2. Create a function to test if a matrix is unholy - Check each 1 bit to ensure it has an adjacent 1 - Use bit operations to check neighbors 3. Create a dynamic programming solution - State: (previous row, current row, number of rows processed) - For each state, try all possible next rows - Use memoization to store results 4. Main program to initialize and run the DP Here's the implementation:
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 | #include <stdio.h> #include <string.h> // DP table dimensions #define ROW_BITS 8 #define MAX_ROWS 8 #define MAX_ROW_VAL (1 << ROW_BITS) // Store results in DP table unsigned long long dp[MAX_ROW_VAL][MAX_ROW_VAL][MAX_ROWS]; int computed[MAX_ROW_VAL][MAX_ROW_VAL][MAX_ROWS]; // Check if two consecutive rows make valid unholy pattern int is_valid_rows(unsigned char prev_row, unsigned char curr_row) { // Check if any 1 in prev_row is isolated (no 1s adjacent in curr_row) unsigned char mask = prev_row; while (mask) { int pos = __builtin_ctz(mask); // Get position of least significant 1 if ((prev_row & (1 << pos)) && // If there's a 1 here !(curr_row & (1 << pos))) { // And no 1 below // Check left and right in same row int has_neighbor = 0; if (pos > 0 && (prev_row & (1 << (pos-1)))) has_neighbor = 1; if (pos < ROW_BITS-1 && (prev_row & (1 << (pos+1)))) has_neighbor = 1; if (!has_neighbor) return 0; } mask &= (mask - 1); // Clear least significant 1 } return 1; } // Dynamic programming function unsigned long long solve(unsigned char prev_row, unsigned char curr_row, int row_num) { // Base case: reached end of matrix if (row_num == MAX_ROWS) { // Check if last row is valid return is_valid_rows(curr_row, 0); } // Return memoized result if available if (computed[prev_row][curr_row][row_num]) { return dp[prev_row][curr_row][row_num]; } unsigned long long result = 0; // Try all possible next rows for (int next_row = 0; next_row < MAX_ROW_VAL; next_row++) { // Check if current configuration is valid if (is_valid_rows(prev_row, curr_row) && is_valid_rows(curr_row, next_row)) { result += solve(curr_row, next_row, row_num + 1); } } // Memoize and return computed[prev_row][curr_row][row_num] = 1; dp[prev_row][curr_row][row_num] = result; return result; } int main() { unsigned long long total = 0; memset(computed, 0, sizeof(computed)); memset(dp, 0, sizeof(dp)); // Try all possible first two rows for (int first_row = 0; first_row < MAX_ROW_VAL; first_row++) { for (int second_row = 0; second_row < MAX_ROW_VAL; second_row++) { if (is_valid_rows(first_row, second_row)) { total += solve(first_row, second_row, 2); } } } printf("Total number of unholy matrices: %llu\n", total); return 0; } |
I extracted the following code from that output:
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 | #include <stdio.h> #include <string.h> // DP table dimensions #define ROW_BITS 8 #define MAX_ROWS 8 #define MAX_ROW_VAL (1 << ROW_BITS) // Store results in DP table unsigned long long dp[MAX_ROW_VAL][MAX_ROW_VAL][MAX_ROWS]; int computed[MAX_ROW_VAL][MAX_ROW_VAL][MAX_ROWS]; // Check if two consecutive rows make valid unholy pattern int is_valid_rows(unsigned char prev_row, unsigned char curr_row) { // Check if any 1 in prev_row is isolated (no 1s adjacent in curr_row) unsigned char mask = prev_row; while (mask) { int pos = __builtin_ctz(mask); // Get position of least significant 1 if ((prev_row & (1 << pos)) && // If there's a 1 here !(curr_row & (1 << pos))) { // And no 1 below // Check left and right in same row int has_neighbor = 0; if (pos > 0 && (prev_row & (1 << (pos-1)))) has_neighbor = 1; if (pos < ROW_BITS-1 && (prev_row & (1 << (pos+1)))) has_neighbor = 1; if (!has_neighbor) return 0; } mask &= (mask - 1); // Clear least significant 1 } return 1; } // Dynamic programming function unsigned long long solve(unsigned char prev_row, unsigned char curr_row, int row_num) { // Base case: reached end of matrix if (row_num == MAX_ROWS) { // Check if last row is valid return is_valid_rows(curr_row, 0); } // Return memoized result if available if (computed[prev_row][curr_row][row_num]) { return dp[prev_row][curr_row][row_num]; } unsigned long long result = 0; // Try all possible next rows for (int next_row = 0; next_row < MAX_ROW_VAL; next_row++) { // Check if current configuration is valid if (is_valid_rows(prev_row, curr_row) && is_valid_rows(curr_row, next_row)) { result += solve(curr_row, next_row, row_num + 1); } } // Memoize and return computed[prev_row][curr_row][row_num] = 1; dp[prev_row][curr_row][row_num] = result; return result; } int main() { unsigned long long total = 0; memset(computed, 0, sizeof(computed)); memset(dp, 0, sizeof(dp)); // Try all possible first two rows for (int first_row = 0; first_row < MAX_ROW_VAL; first_row++) { for (int second_row = 0; second_row < MAX_ROW_VAL; second_row++) { if (is_valid_rows(first_row, second_row)) { total += solve(first_row, second_row, 2); } } } printf("Total number of unholy matrices: %llu\n", total); return 0; } |
Running the following program:
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 | #include <stdio.h> #include <string.h> // DP table dimensions #define ROW_BITS 8 #define MAX_ROWS 8 #define MAX_ROW_VAL (1 << ROW_BITS) // Store results in DP table unsigned long long dp[MAX_ROW_VAL][MAX_ROW_VAL][MAX_ROWS]; int computed[MAX_ROW_VAL][MAX_ROW_VAL][MAX_ROWS]; // Check if two consecutive rows make valid unholy pattern int is_valid_rows(unsigned char prev_row, unsigned char curr_row) { // Check if any 1 in prev_row is isolated (no 1s adjacent in curr_row) unsigned char mask = prev_row; while (mask) { int pos = __builtin_ctz(mask); // Get position of least significant 1 if ((prev_row & (1 << pos)) && // If there's a 1 here !(curr_row & (1 << pos))) { // And no 1 below // Check left and right in same row int has_neighbor = 0; if (pos > 0 && (prev_row & (1 << (pos-1)))) has_neighbor = 1; if (pos < ROW_BITS-1 && (prev_row & (1 << (pos+1)))) has_neighbor = 1; if (!has_neighbor) return 0; } mask &= (mask - 1); // Clear least significant 1 } return 1; } // Dynamic programming function unsigned long long solve(unsigned char prev_row, unsigned char curr_row, int row_num) { // Base case: reached end of matrix if (row_num == MAX_ROWS) { // Check if last row is valid return is_valid_rows(curr_row, 0); } // Return memoized result if available if (computed[prev_row][curr_row][row_num]) { return dp[prev_row][curr_row][row_num]; } unsigned long long result = 0; // Try all possible next rows for (int next_row = 0; next_row < MAX_ROW_VAL; next_row++) { // Check if current configuration is valid if (is_valid_rows(prev_row, curr_row) && is_valid_rows(curr_row, next_row)) { result += solve(curr_row, next_row, row_num + 1); } } // Memoize and return computed[prev_row][curr_row][row_num] = 1; dp[prev_row][curr_row][row_num] = result; return result; } int main() { unsigned long long total = 0; memset(computed, 0, sizeof(computed)); memset(dp, 0, sizeof(dp)); // Try all possible first two rows for (int first_row = 0; first_row < MAX_ROW_VAL; first_row++) { for (int second_row = 0; second_row < MAX_ROW_VAL; second_row++) { if (is_valid_rows(first_row, second_row)) { total += solve(first_row, second_row, 2); } } } printf("Total number of unholy matrices: %llu\n", total); return 0; } |
Total number of unholy matrices: 53003772538202116
Testing if the previous output contains the string 1121231537486377866
: False
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
Let's break this down into a clear plan and then implement it. Plan: 1. Represent the 8x8 matrix using an unsigned long (64 bits) 2. Create a function to test if a matrix is unholy: - For each 1 in the matrix, check if it has a neighboring 1 - Use bit operations to check neighbors efficiently 3. Create a dynamic programming solution: - State will be (current_rows, last_two_rows) - For each state, try all possible next two rows - Base case is when we reach 8 rows - Use a 2D array to store intermediate results 4. Main program structure: - Initialize DP array - Call recursive function starting with 0 rows - Print final result Here's the implementation:
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 | #include <stdio.h> #include <string.h> // DP array: [number of rows][previous two rows pattern] unsigned long long dp[9][65536]; int calculated[9][65536]; // Check if a specific row configuration is valid with previous rows int is_valid_rows(unsigned int prev_two_rows, unsigned int next_two_rows) { unsigned int top_row = (prev_two_rows >> 8) & 0xFF; unsigned int middle_row = prev_two_rows & 0xFF; unsigned int bottom_row = (next_two_rows >> 8) & 0xFF; unsigned int last_row = next_two_rows & 0xFF; // Check middle row's 1s have neighbors for(int i = 0; i < 8; i++) { if((middle_row & (1 << i)) != 0) { unsigned int mask = 1 << i; unsigned int has_neighbor = (i > 0 && (middle_row & (mask >> 1))) || (i < 7 && (middle_row & (mask << 1))) || (top_row & mask) || (bottom_row & mask); if(!has_neighbor) return 0; } } // Check bottom row's 1s have neighbors (except for last row case) if(next_two_rows != 0) { for(int i = 0; i < 8; i++) { if((bottom_row & (1 << i)) != 0) { unsigned int mask = 1 << i; unsigned int has_neighbor = (i > 0 && (bottom_row & (mask >> 1))) || (i < 7 && (bottom_row & (mask << 1))) || (middle_row & mask) || (last_row & mask); if(!has_neighbor) return 0; } } } return 1; } // Recursive function to count unholy matrices unsigned long long count_unholy(int row, unsigned int prev_two_rows) { // Base case: reached end of matrix if(row == 8) return 1; // Return memoized result if available if(calculated[row][prev_two_rows]) return dp[row][prev_two_rows]; unsigned long long result = 0; // Try all possible next two rows for(unsigned int next_two_rows = 0; next_two_rows < 65536; next_two_rows++) { if(is_valid_rows(prev_two_rows, next_two_rows)) { result += count_unholy(row + 2, next_two_rows); } } calculated[row][prev_two_rows] = 1; dp[row][prev_two_rows] = result; return result; } int main() { // Initialize memoization arrays memset(calculated, 0, sizeof(calculated)); memset(dp, 0, sizeof(dp)); // Start counting from row 0 with no previous rows unsigned long long result = count_unholy(0, 0); printf("Total number of unholy 8x8 matrices: %llu\n", result); return 0; } |
I extracted the following code from that output:
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 | C #include <stdio.h> #include <string.h> // DP array: [number of rows][previous two rows pattern] unsigned long long dp[9][65536]; int calculated[9][65536]; // Check if a specific row configuration is valid with previous rows int is_valid_rows(unsigned int prev_two_rows, unsigned int next_two_rows) { unsigned int top_row = (prev_two_rows >> 8) & 0xFF; unsigned int middle_row = prev_two_rows & 0xFF; unsigned int bottom_row = (next_two_rows >> 8) & 0xFF; unsigned int last_row = next_two_rows & 0xFF; // Check middle row's 1s have neighbors for(int i = 0; i < 8; i++) { if((middle_row & (1 << i)) != 0) { unsigned int mask = 1 << i; unsigned int has_neighbor = (i > 0 && (middle_row & (mask >> 1))) || (i < 7 && (middle_row & (mask << 1))) || (top_row & mask) || (bottom_row & mask); if(!has_neighbor) return 0; } } // Check bottom row's 1s have neighbors (except for last row case) if(next_two_rows != 0) { for(int i = 0; i < 8; i++) { if((bottom_row & (1 << i)) != 0) { unsigned int mask = 1 << i; unsigned int has_neighbor = (i > 0 && (bottom_row & (mask >> 1))) || (i < 7 && (bottom_row & (mask << 1))) || (middle_row & mask) || (last_row & mask); if(!has_neighbor) return 0; } } } return 1; } // Recursive function to count unholy matrices unsigned long long count_unholy(int row, unsigned int prev_two_rows) { // Base case: reached end of matrix if(row == 8) return 1; // Return memoized result if available if(calculated[row][prev_two_rows]) return dp[row][prev_two_rows]; unsigned long long result = 0; // Try all possible next two rows for(unsigned int next_two_rows = 0; next_two_rows < 65536; next_two_rows++) { if(is_valid_rows(prev_two_rows, next_two_rows)) { result += count_unholy(row + 2, next_two_rows); } } calculated[row][prev_two_rows] = 1; dp[row][prev_two_rows] = result; return result; } int main() { // Initialize memoization arrays memset(calculated, 0, sizeof(calculated)); memset(dp, 0, sizeof(dp)); // Start counting from row 0 with no previous rows unsigned long long result = count_unholy(0, 0); printf("Total number of unholy 8x8 matrices: %llu\n", result); return 0; } |
Running the following program:
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 | C #include <stdio.h> #include <string.h> // DP array: [number of rows][previous two rows pattern] unsigned long long dp[9][65536]; int calculated[9][65536]; // Check if a specific row configuration is valid with previous rows int is_valid_rows(unsigned int prev_two_rows, unsigned int next_two_rows) { unsigned int top_row = (prev_two_rows >> 8) & 0xFF; unsigned int middle_row = prev_two_rows & 0xFF; unsigned int bottom_row = (next_two_rows >> 8) & 0xFF; unsigned int last_row = next_two_rows & 0xFF; // Check middle row's 1s have neighbors for(int i = 0; i < 8; i++) { if((middle_row & (1 << i)) != 0) { unsigned int mask = 1 << i; unsigned int has_neighbor = (i > 0 && (middle_row & (mask >> 1))) || (i < 7 && (middle_row & (mask << 1))) || (top_row & mask) || (bottom_row & mask); if(!has_neighbor) return 0; } } // Check bottom row's 1s have neighbors (except for last row case) if(next_two_rows != 0) { for(int i = 0; i < 8; i++) { if((bottom_row & (1 << i)) != 0) { unsigned int mask = 1 << i; unsigned int has_neighbor = (i > 0 && (bottom_row & (mask >> 1))) || (i < 7 && (bottom_row & (mask << 1))) || (middle_row & mask) || (last_row & mask); if(!has_neighbor) return 0; } } } return 1; } // Recursive function to count unholy matrices unsigned long long count_unholy(int row, unsigned int prev_two_rows) { // Base case: reached end of matrix if(row == 8) return 1; // Return memoized result if available if(calculated[row][prev_two_rows]) return dp[row][prev_two_rows]; unsigned long long result = 0; // Try all possible next two rows for(unsigned int next_two_rows = 0; next_two_rows < 65536; next_two_rows++) { if(is_valid_rows(prev_two_rows, next_two_rows)) { result += count_unholy(row + 2, next_two_rows); } } calculated[row][prev_two_rows] = 1; dp[row][prev_two_rows] = result; return result; } int main() { // Initialize memoization arrays memset(calculated, 0, sizeof(calculated)); memset(dp, 0, sizeof(dp)); // Start counting from row 0 with no previous rows unsigned long long result = count_unholy(0, 0); printf("Total number of unholy 8x8 matrices: %llu\n", result); return 0; } |
main.c:1:2: error: expected ';' before 'typedef'
1 | C
| ^
| ;
main.sh: line 2: ./a.out: No such file or directory
Testing if the previous output contains the string 1121231537486377866
: False
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
Let's break this down into a clear plan and then implement it. Plan: 1. Represent the 8x8 matrix using an unsigned long (64 bits) 2. Create a function to test if a matrix is unholy: - For each 1 in the matrix, check if it has another 1 adjacent to it - Use bit operations to check adjacency 3. Create a dynamic programming solution: - State: current row pair and previous row pair - Base case: when we've filled all 8 rows - For each state, try all possible combinations for the next row pair - Memoize results using a hash table or array 4. Main program: - Initialize memoization structure - Call recursive function starting with first two rows - Return final count Here's the implementation:
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 | #include <stdio.h> #include <string.h> // Memoization table unsigned long long memo[256][256]; // [prev_rows][curr_rows] // Check if a three-row sequence contains any isolated 1s in the middle row int has_isolated_ones(unsigned int top, unsigned int mid, unsigned int bot) { unsigned int isolated; // A 1 is not isolated if it has a neighbor above, below, left, or right // Get all 1s in middle row unsigned int ones = mid; // Get ones that have neighbors above or below unsigned int vertical_neighbors = top | bot; // Get ones that have neighbors to the left or right unsigned int horizontal_neighbors = (mid << 1) | (mid >> 1); // A 1 is isolated if it has no neighbors isolated = ones & ~vertical_neighbors & ~horizontal_neighbors; return isolated != 0; } // Recursive function to count unholy matrices unsigned long long count_unholy(int row, unsigned int prev_pair, unsigned int curr_pair) { // Base case: we've filled all rows if (row >= 7) return 1; // Check memoization table if (memo[prev_pair][curr_pair] != -1) return memo[prev_pair][curr_pair]; unsigned long long count = 0; unsigned int prev_top = (prev_pair >> 8) & 0xFF; unsigned int prev_bot = prev_pair & 0xFF; unsigned int curr_top = (curr_pair >> 8) & 0xFF; unsigned int curr_bot = curr_pair & 0xFF; // Try all possibilities for next row pair for (unsigned int next_pair = 0; next_pair < (1 << 16); next_pair++) { unsigned int next_top = (next_pair >> 8) & 0xFF; unsigned int next_bot = next_pair & 0xFF; // Check if current configuration creates any isolated ones if (!has_isolated_ones(prev_bot, curr_top, next_top) && !has_isolated_ones(curr_top, curr_bot, next_bot)) { count += count_unholy(row + 2, curr_pair, next_pair); } } memo[prev_pair][curr_pair] = count; return count; } int main() { unsigned long long total = 0; // Initialize memoization table memset(memo, -1, sizeof(memo)); // Try all possibilities for first two rows for (unsigned int first_pair = 0; first_pair < (1 << 16); first_pair++) { unsigned int top = (first_pair >> 8) & 0xFF; unsigned int bot = first_pair & 0xFF; // Check if first two rows are valid (no isolated ones in first row) if (!has_isolated_ones(0, top, bot)) { total += count_unholy(2, 0, first_pair); } } printf("Total number of unholy 8x8 matrices: %llu\n", total); return 0; } |
I extracted the following code from that output:
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 | #include <stdio.h> #include <string.h> // Memoization table unsigned long long memo[256][256]; // [prev_rows][curr_rows] // Check if a three-row sequence contains any isolated 1s in the middle row int has_isolated_ones(unsigned int top, unsigned int mid, unsigned int bot) { unsigned int isolated; // A 1 is not isolated if it has a neighbor above, below, left, or right // Get all 1s in middle row unsigned int ones = mid; // Get ones that have neighbors above or below unsigned int vertical_neighbors = top | bot; // Get ones that have neighbors to the left or right unsigned int horizontal_neighbors = (mid << 1) | (mid >> 1); // A 1 is isolated if it has no neighbors isolated = ones & ~vertical_neighbors & ~horizontal_neighbors; return isolated != 0; } // Recursive function to count unholy matrices unsigned long long count_unholy(int row, unsigned int prev_pair, unsigned int curr_pair) { // Base case: we've filled all rows if (row >= 7) return 1; // Check memoization table if (memo[prev_pair][curr_pair] != -1) return memo[prev_pair][curr_pair]; unsigned long long count = 0; unsigned int prev_top = (prev_pair >> 8) & 0xFF; unsigned int prev_bot = prev_pair & 0xFF; unsigned int curr_top = (curr_pair >> 8) & 0xFF; unsigned int curr_bot = curr_pair & 0xFF; // Try all possibilities for next row pair for (unsigned int next_pair = 0; next_pair < (1 << 16); next_pair++) { unsigned int next_top = (next_pair >> 8) & 0xFF; unsigned int next_bot = next_pair & 0xFF; // Check if current configuration creates any isolated ones if (!has_isolated_ones(prev_bot, curr_top, next_top) && !has_isolated_ones(curr_top, curr_bot, next_bot)) { count += count_unholy(row + 2, curr_pair, next_pair); } } memo[prev_pair][curr_pair] = count; return count; } int main() { unsigned long long total = 0; // Initialize memoization table memset(memo, -1, sizeof(memo)); // Try all possibilities for first two rows for (unsigned int first_pair = 0; first_pair < (1 << 16); first_pair++) { unsigned int top = (first_pair >> 8) & 0xFF; unsigned int bot = first_pair & 0xFF; // Check if first two rows are valid (no isolated ones in first row) if (!has_isolated_ones(0, top, bot)) { total += count_unholy(2, 0, first_pair); } } printf("Total number of unholy 8x8 matrices: %llu\n", total); return 0; } |
Running the following program:
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 | #include <stdio.h> #include <string.h> // Memoization table unsigned long long memo[256][256]; // [prev_rows][curr_rows] // Check if a three-row sequence contains any isolated 1s in the middle row int has_isolated_ones(unsigned int top, unsigned int mid, unsigned int bot) { unsigned int isolated; // A 1 is not isolated if it has a neighbor above, below, left, or right // Get all 1s in middle row unsigned int ones = mid; // Get ones that have neighbors above or below unsigned int vertical_neighbors = top | bot; // Get ones that have neighbors to the left or right unsigned int horizontal_neighbors = (mid << 1) | (mid >> 1); // A 1 is isolated if it has no neighbors isolated = ones & ~vertical_neighbors & ~horizontal_neighbors; return isolated != 0; } // Recursive function to count unholy matrices unsigned long long count_unholy(int row, unsigned int prev_pair, unsigned int curr_pair) { // Base case: we've filled all rows if (row >= 7) return 1; // Check memoization table if (memo[prev_pair][curr_pair] != -1) return memo[prev_pair][curr_pair]; unsigned long long count = 0; unsigned int prev_top = (prev_pair >> 8) & 0xFF; unsigned int prev_bot = prev_pair & 0xFF; unsigned int curr_top = (curr_pair >> 8) & 0xFF; unsigned int curr_bot = curr_pair & 0xFF; // Try all possibilities for next row pair for (unsigned int next_pair = 0; next_pair < (1 << 16); next_pair++) { unsigned int next_top = (next_pair >> 8) & 0xFF; unsigned int next_bot = next_pair & 0xFF; // Check if current configuration creates any isolated ones if (!has_isolated_ones(prev_bot, curr_top, next_top) && !has_isolated_ones(curr_top, curr_bot, next_bot)) { count += count_unholy(row + 2, curr_pair, next_pair); } } memo[prev_pair][curr_pair] = count; return count; } int main() { unsigned long long total = 0; // Initialize memoization table memset(memo, -1, sizeof(memo)); // Try all possibilities for first two rows for (unsigned int first_pair = 0; first_pair < (1 << 16); first_pair++) { unsigned int top = (first_pair >> 8) & 0xFF; unsigned int bot = first_pair & 0xFF; // Check if first two rows are valid (no isolated ones in first row) if (!has_isolated_ones(0, top, bot)) { total += count_unholy(2, 0, first_pair); } } printf("Total number of unholy 8x8 matrices: %llu\n", total); return 0; } |
Total number of unholy 8x8 matrices: 4475378688
Testing if the previous output contains the string 1121231537486377866
: False
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
A binary 8x8 matrix is 'unholy' if there are no isolated 1s. A 1 is isolated if there isn't another 1 in any of the 4 direct cardinal directions. Write a C program that counts the total number of unholy 8x8 matricies.To solve this question: - Use bit arithmetic and an unsigned long to represent the matrix. - Write a function is_unholy that tests if a matrix is unholy by bit-shifting and masking. Use a dynamic program to count the number of unholy matricies. - Recurse on the number of rows the matrix has. - Enumerate all 2^16 next two rows. This is enough to completely isolate the prior solutions from the next. Write out a plan for the program, and then implement the plan in C.
Let's break this down into a clear plan and then implement it. Plan: 1. Represent the 8x8 matrix using 64 bits (unsigned long long) 2. Create helper functions: - is_unholy(): Check if a matrix has no isolated 1s - get_bit(): Get a specific bit from the matrix - count_unholy(): Main dynamic programming function 3. Dynamic Programming Approach: - State: (current_rows, previous_two_rows) - For each state, try all possible next two rows - Check if current configuration is valid - Base case: When all 8 rows are filled - Use memoization to store results 4. Main steps: - Initialize memoization table - Start recursion from row 0 - Sum up all valid configurations Here's the implementation:
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 | #include <stdio.h> #include <string.h> #define ROWS 8 #define COLS 8 #define MAX_TWO_ROWS (1 << 16) unsigned long long memo[ROWS/2][MAX_TWO_ROWS]; int computed[ROWS/2][MAX_TWO_ROWS]; // Get bit at position (row, col) int get_bit(unsigned long long matrix, int row, int col) { return (matrix >> (row * COLS + col)) & 1; } // Check if a 1 at (row, col) is isolated int is_isolated(unsigned long long matrix, int row, int col) { if (!get_bit(matrix, row, col)) return 0; // Check four directions if (row > 0 && get_bit(matrix, row-1, col)) return 0; if (row < ROWS-1 && get_bit(matrix, row+1, col)) return 0; if (col > 0 && get_bit(matrix, row, col-1)) return 0; if (col < COLS-1 && get_bit(matrix, row, col+1)) return 0; return 1; } // Check if matrix has any isolated 1s int has_isolated_ones(unsigned long long matrix) { for(int i = 0; i < ROWS; i++) { for(int j = 0; j < COLS; j++) { if (is_isolated(matrix, i, j)) return 1; } } return 0; } // Recursive function to count unholy matrices unsigned long long count_unholy(int current_row, unsigned int prev_two_rows) { // Base case: all rows filled if (current_row == ROWS/2) return 1; // Check memoization if (computed[current_row][prev_two_rows]) return memo[current_row][prev_two_rows]; unsigned long long count = 0; // Try all possible next two rows for(unsigned int next_two_rows = 0; next_two_rows < MAX_TWO_ROWS; next_two_rows++) { unsigned long long partial_matrix = 0; // Construct partial matrix for validation if (current_row > 0) { partial_matrix |= ((unsigned long long)prev_two_rows) << (2*COLS*(current_row-1)); } partial_matrix |= ((unsigned long long)next_two_rows) << (2*COLS*current_row); // Check if this partial configuration is valid if (!has_isolated_ones(partial_matrix)) { count += count_unholy(current_row + 1, next_two_rows); } } computed[current_row][prev_two_rows] = 1; memo[current_row][prev_two_rows] = count; return count; } int main() { // Initialize memoization arrays memset(computed, 0, sizeof(computed)); memset(memo, 0, sizeof(memo)); // Start counting from row 0 with empty previous rows unsigned long long result = count_unholy(0, 0); printf("Number of unholy 8x8 matrices: %llu\n", result); return 0; } |
I extracted the following code from that output:
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 | #include <stdio.h> #include <string.h> #define ROWS 8 #define COLS 8 #define MAX_TWO_ROWS (1 << 16) unsigned long long memo[ROWS/2][MAX_TWO_ROWS]; int computed[ROWS/2][MAX_TWO_ROWS]; // Get bit at position (row, col) int get_bit(unsigned long long matrix, int row, int col) { return (matrix >> (row * COLS + col)) & 1; } // Check if a 1 at (row, col) is isolated int is_isolated(unsigned long long matrix, int row, int col) { if (!get_bit(matrix, row, col)) return 0; // Check four directions if (row > 0 && get_bit(matrix, row-1, col)) return 0; if (row < ROWS-1 && get_bit(matrix, row+1, col)) return 0; if (col > 0 && get_bit(matrix, row, col-1)) return 0; if (col < COLS-1 && get_bit(matrix, row, col+1)) return 0; return 1; } // Check if matrix has any isolated 1s int has_isolated_ones(unsigned long long matrix) { for(int i = 0; i < ROWS; i++) { for(int j = 0; j < COLS; j++) { if (is_isolated(matrix, i, j)) return 1; } } return 0; } // Recursive function to count unholy matrices unsigned long long count_unholy(int current_row, unsigned int prev_two_rows) { // Base case: all rows filled if (current_row == ROWS/2) return 1; // Check memoization if (computed[current_row][prev_two_rows]) return memo[current_row][prev_two_rows]; unsigned long long count = 0; // Try all possible next two rows for(unsigned int next_two_rows = 0; next_two_rows < MAX_TWO_ROWS; next_two_rows++) { unsigned long long partial_matrix = 0; // Construct partial matrix for validation if (current_row > 0) { partial_matrix |= ((unsigned long long)prev_two_rows) << (2*COLS*(current_row-1)); } partial_matrix |= ((unsigned long long)next_two_rows) << (2*COLS*current_row); // Check if this partial configuration is valid if (!has_isolated_ones(partial_matrix)) { count += count_unholy(current_row + 1, next_two_rows); } } computed[current_row][prev_two_rows] = 1; memo[current_row][prev_two_rows] = count; return count; } int main() { // Initialize memoization arrays memset(computed, 0, sizeof(computed)); memset(memo, 0, sizeof(memo)); // Start counting from row 0 with empty previous rows unsigned long long result = count_unholy(0, 0); printf("Number of unholy 8x8 matrices: %llu\n", result); return 0; } |
Running the following program:
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 | #include <stdio.h> #include <string.h> #define ROWS 8 #define COLS 8 #define MAX_TWO_ROWS (1 << 16) unsigned long long memo[ROWS/2][MAX_TWO_ROWS]; int computed[ROWS/2][MAX_TWO_ROWS]; // Get bit at position (row, col) int get_bit(unsigned long long matrix, int row, int col) { return (matrix >> (row * COLS + col)) & 1; } // Check if a 1 at (row, col) is isolated int is_isolated(unsigned long long matrix, int row, int col) { if (!get_bit(matrix, row, col)) return 0; // Check four directions if (row > 0 && get_bit(matrix, row-1, col)) return 0; if (row < ROWS-1 && get_bit(matrix, row+1, col)) return 0; if (col > 0 && get_bit(matrix, row, col-1)) return 0; if (col < COLS-1 && get_bit(matrix, row, col+1)) return 0; return 1; } // Check if matrix has any isolated 1s int has_isolated_ones(unsigned long long matrix) { for(int i = 0; i < ROWS; i++) { for(int j = 0; j < COLS; j++) { if (is_isolated(matrix, i, j)) return 1; } } return 0; } // Recursive function to count unholy matrices unsigned long long count_unholy(int current_row, unsigned int prev_two_rows) { // Base case: all rows filled if (current_row == ROWS/2) return 1; // Check memoization if (computed[current_row][prev_two_rows]) return memo[current_row][prev_two_rows]; unsigned long long count = 0; // Try all possible next two rows for(unsigned int next_two_rows = 0; next_two_rows < MAX_TWO_ROWS; next_two_rows++) { unsigned long long partial_matrix = 0; // Construct partial matrix for validation if (current_row > 0) { partial_matrix |= ((unsigned long long)prev_two_rows) << (2*COLS*(current_row-1)); } partial_matrix |= ((unsigned long long)next_two_rows) << (2*COLS*current_row); // Check if this partial configuration is valid if (!has_isolated_ones(partial_matrix)) { count += count_unholy(current_row + 1, next_two_rows); } } computed[current_row][prev_two_rows] = 1; memo[current_row][prev_two_rows] = count; return count; } int main() { // Initialize memoization arrays memset(computed, 0, sizeof(computed)); memset(memo, 0, sizeof(memo)); // Start counting from row 0 with empty previous rows unsigned long long result = count_unholy(0, 0); printf("Number of unholy 8x8 matrices: %llu\n", result); return 0; } |
Timeout: function took too long to complete
Testing if the previous output contains the string 1121231537486377866
: False