Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
The function `count` calculates the number of stable configurations in an 8x8 grid, where a cell is considered stable if all its neighbors (top, left, bottom, right) are 0 and the cell itself is 1. Here are a few ways to make the function shorter: 1. Remove the `ROWS` and `COLS` variables and use the values directly. 2. Use bit manipulation to update the cell values instead of using conditional statements. 3. Combine the initialization of `array` and `init` into a single line. 4. Use a single loop instead of nested loops to iterate over the cells. Here's the shortened version of the function:
1 2 3 4 5 6 7 8 9 10 11 | int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 49; j += 8) for (int k = 1; k < 7; k++) t ^= ((((t >> (j + k - 9)) & 1) + ((t >> (j + k - 1)) & 1) + ((t >> (j + k + 7)) & 1) + ((t >> (j + k + 1)) & 1) == 0) && ((t >> (j + k)) & 1)) << (j + k); c += (a == t); } return c; } |
1 2 3 4 5 6 7 8 9 10 11 | int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 49; j += 8) for (int k = 1; k < 7; k++) t ^= (!((t >> (j + k - 9) & 1) + (t >> (j + k - 1) & 1) + (t >> (j + k + 7) & 1) + (t >> (j + k + 1) & 1)) && (t >> (j + k) & 1)) << (j + k); c += (a == t); } return c; } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 13 | #include <stdio.h> int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 49; j += 8) for (int k = 1; k < 7; k++) t ^= (!((t >> (j + k - 9) & 1) + (t >> (j + k - 1) & 1) + (t >> (j + k + 7) & 1) + (t >> (j + k + 1) & 1)) && (t >> (j + k) & 1)) << (j + k); c += (a == t); } return c; } |
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 | #include <stdio.h> int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 49; j += 8) for (int k = 1; k < 7; k++) t ^= (!((t >> (j + k - 9) & 1) + (t >> (j + k - 1) & 1) + (t >> (j + k + 7) & 1) + (t >> (j + k + 1) & 1)) && (t >> (j + k) & 1)) << (j + k); c += (a == t); } return c; } #include<stdio.h> #include<stdlib.h> int main() { int answer = count(); int expected = 27488; if (answer != expected) { printf("Wrong answer; got %d instead of %d.\n", answer, expected); exit(1); } printf("All tests passed\n"); } |
Wrong answer; got 36880 instead of 27488.
Testing if the previous output contains the string All tests passed
: False
Resulting in output: True
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
The function `count` calculates the number of configurations in an 8x8 grid where all cells that have no neighboring cells (top, left, bottom, right) with a value of 1 remain unchanged after one iteration. Here's a shorter version of the function:
1 2 3 4 5 6 7 8 9 10 11 12 13 | int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 7; j++) for (int k = 1; k < 7; k++) { int p = j * 8 + k, s = ((t >> (p - 1)) & 1) + ((t >> (p - 8)) & 1) + ((t >> (p + 1)) & 1) + ((t >> (p + 8)) & 1); if (s == 0 && ((t >> p) & 1)) a &= ~(1ULL << p); } c += (a == t); } return c; } |
1 2 3 4 5 6 7 8 9 10 11 12 | int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 9; j < 55; j += 8) for (int k = 1; k < 7; k++) if (((t >> (j + k - 1)) & 1) + ((t >> (j + k - 8)) & 1) + ((t >> (j + k + 1)) & 1) + ((t >> (j + k + 8)) & 1) == 0 && ((t >> (j + k)) & 1)) a &= ~(1ULL << (j + k)); c += (a == t); } return c; } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 | #include <stdint.h> int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 9; j < 55; j += 8) for (int k = 1; k < 7; k++) if (((t >> (j + k - 1)) & 1) + ((t >> (j + k - 8)) & 1) + ((t >> (j + k + 1)) & 1) + ((t >> (j + k + 8)) & 1) == 0 && ((t >> (j + k)) & 1)) a &= ~(1ULL << (j + k)); c += (a == t); } return c; } |
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 | #include <stdint.h> int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 9; j < 55; j += 8) for (int k = 1; k < 7; k++) if (((t >> (j + k - 1)) & 1) + ((t >> (j + k - 8)) & 1) + ((t >> (j + k + 1)) & 1) + ((t >> (j + k + 8)) & 1) == 0 && ((t >> (j + k)) & 1)) a &= ~(1ULL << (j + k)); c += (a == t); } return c; } #include<stdio.h> #include<stdlib.h> int main() { int answer = count(); int expected = 27488; if (answer != expected) { printf("Wrong answer; got %d instead of %d.\n", answer, expected); exit(1); } printf("All tests passed\n"); } |
Wrong answer; got 36608 instead of 27488.
Testing if the previous output contains the string All tests passed
: False
Resulting in output: False
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
The function `count` calculates the number of stable configurations in a cellular automaton on an 8x8 grid. It iterates through all possible 16-bit configurations, where each bit represents a cell in the grid. For each configuration, it checks the neighbors of each cell and updates the cell if all neighbors are 0 and the cell itself is 1. Finally, it counts the number of configurations that remain unchanged after the update process. Here are a few ways to make the function shorter: 1. Remove the unnecessary variables `ROWS` and `COLS` and use the constant values directly. 2. Simplify the bit manipulation operations by using bitwise shifts and masks. 3. Combine the loop conditions and update statements into a single line. 4. Use a single loop instead of nested loops to iterate through the grid cells. Here's a shortened version of the `count` function:
1 2 3 4 5 6 7 8 9 10 11 | int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 63; j++) if (((t >> j) & 1) && !((t >> (j - 1)) & 1) && !((t >> (j + 1)) & 1) && !((t >> (j - 8)) & 1) && !((t >> (j + 8)) & 1)) a &= ~(1ULL << j); c += (a == t); } return c; } |
1 2 3 4 5 6 7 8 9 10 | int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 63; j++) a &= ~(((t >> j) & 1) && !((t >> (j - 1)) & 1) && !((t >> (j + 1)) & 1) && !((t >> (j - 8)) & 1) && !((t >> (j + 8)) & 1) ? (1ULL << j) : 0); c += (a == t); } return c; } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 | #include <stdint.h> int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 63; j++) a &= ~(((t >> j) & 1) && !((t >> (j - 1)) & 1) && !((t >> (j + 1)) & 1) && !((t >> (j - 8)) & 1) && !((t >> (j + 8)) & 1) ? (1ULL << j) : 0); c += (a == t); } return c; } |
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 | #include <stdint.h> int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), t = a; for (int j = 1; j < 63; j++) a &= ~(((t >> j) & 1) && !((t >> (j - 1)) & 1) && !((t >> (j + 1)) & 1) && !((t >> (j - 8)) & 1) && !((t >> (j + 8)) & 1) ? (1ULL << j) : 0); c += (a == t); } return c; } #include<stdio.h> #include<stdlib.h> int main() { int answer = count(); int expected = 27488; if (answer != expected) { printf("Wrong answer; got %d instead of %d.\n", answer, expected); exit(1); } printf("All tests passed\n"); } |
All tests passed
Testing if the previous output contains the string All tests passed
: True
Resulting in output: True
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
The function `count` takes no arguments and returns an integer. It counts the number of 4x4 binary matrices where all cells that have a value of 1 and are surrounded by cells with a value of 0 are flipped to 0 in a single iteration. To make the function shorter, we can: 1. Remove the constants `ROWS` and `COLS` and use their values directly. 2. Use bitwise operators to generate the initial matrix and update the cells. 3. Combine the loop conditions and remove unnecessary variables. Here's the shortened version of the function: Final answer:
1 2 3 4 5 6 7 8 9 10 11 12 | int count(){ int c=0; for(int i=0;i<1<<16;i++){ long long unsigned int a=((i&0xf)<<9)|((i&0xf0)<<13)|((i&0xf00)<<17)|((i&0xf000)<<21),t=a; for(int j=1;j<7;j++)for(int k=1;k<7;k++){ int p=j*8+k,s=(t>>(p-9))&1,l=(t>>(p-1))&1,b=(t>>(p+7))&1,r=(t>>(p+1))&1; if(s+l+b+r==0&&((t>>p)&1))a&=~(1ULL<<p); } c+=a==t; } return c; } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 | int count(){ int c=0; for(int i=0;i<1<<16;i++){ long long unsigned int a=((i&0xf)<<9)|((i&0xf0)<<13)|((i&0xf00)<<17)|((i&0xf000)<<21),t=a; for(int j=1;j<7;j++)for(int k=1;k<7;k++){ int p=j*8+k,s=(t>>(p-9))&1,l=(t>>(p-1))&1,b=(t>>(p+7))&1,r=(t>>(p+1))&1; if(s+l+b+r==0&&((t>>p)&1))a&=~(1ULL<<p); } c+=a==t; } return c; } |
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 | int count(){ int c=0; for(int i=0;i<1<<16;i++){ long long unsigned int a=((i&0xf)<<9)|((i&0xf0)<<13)|((i&0xf00)<<17)|((i&0xf000)<<21),t=a; for(int j=1;j<7;j++)for(int k=1;k<7;k++){ int p=j*8+k,s=(t>>(p-9))&1,l=(t>>(p-1))&1,b=(t>>(p+7))&1,r=(t>>(p+1))&1; if(s+l+b+r==0&&((t>>p)&1))a&=~(1ULL<<p); } c+=a==t; } return c; } #include<stdio.h> #include<stdlib.h> int main() { int answer = count(); int expected = 27488; if (answer != expected) { printf("Wrong answer; got %d instead of %d.\n", answer, expected); exit(1); } printf("All tests passed\n"); } |
Wrong answer; got 15408 instead of 27488.
Testing if the previous output contains the string All tests passed
: False
Resulting in output: True
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
Code golf this function to be a lot shorter. You only get points if it's <300 bytes (not counting whitespace). Keep the function named `count`.
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 | int count() { int ROWS = 8; int COLS = 8; int count = 0; for (int i = 0; i < 1<<16; i++) { long long unsigned int array = ((i & 0xf) << 9) | ((i & 0xf0) << (9 + 8 - 4)) | ((i & 0xf00) << (9 + 8 - 4 + 8 - 4)) | ((i & 0xf000) << (9 + 8 - 4 + 8 - 4 + 8 - 4)); long long unsigned int init = array; long long unsigned int temp = array; for (int i = 1; i < ROWS - 1; i++) { for (int j = 1; j < COLS - 1; j++) { // Calculate bit positions int pos = i * COLS + j; int topPos = (i - 1) * COLS + j; int leftPos = i * COLS + (j - 1); int bottomPos = (i + 1) * COLS + j; int rightPos = i * COLS + (j + 1); // Get the values of the neighbors int cell = (temp >> pos) & 1; int top = (temp >> topPos) & 1; int left = (temp >> leftPos) & 1; int bottom = (temp >> bottomPos) & 1; int right = (temp >> rightPos) & 1; // Sum the values of the neighbors int sum = top + left + bottom + right; // Update the cell if all neighbors are 0 and the cell itself is 1 if (sum == 0 && cell == 1) { array &= ~(1ULL << pos); } } } count += (init == array); } return count; } |
The `count` function performs the following steps: 1. Iterates through all possible 4x4 binary matrices represented as 16-bit integers. 2. For each matrix, it checks if all cells that have a value of 1 and are surrounded by cells with a value of 0 remain unchanged after one iteration. 3. If the matrix remains unchanged, it increments the count. 4. Finally, it returns the total count of matrices that satisfy the condition. Here's a shortened version of the function:
1 2 3 4 5 6 7 8 9 10 11 12 | int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), b = a; for (int j = 1; j < 7; j++) for (int k = 1; k < 7; k++) if (((a >> (j * 8 + k)) & 1) && !((a >> ((j - 1) * 8 + k)) & 1) && !((a >> (j * 8 + k - 1)) & 1) && !((a >> ((j + 1) * 8 + k)) & 1) && !((a >> (j * 8 + k + 1)) & 1)) b &= ~(1ULL << (j * 8 + k)); c += (a == b); } return c; } |
1 2 3 4 5 6 7 8 9 10 11 | int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), b = a; for (int j = 9; j < 55; j += 8) for (int k = 1; k < 7; k++) b &= ~((((a >> (j + k)) & 1) && !((a >> (j + k - 9)) & 1) && !((a >> (j + k - 1)) & 1) && !((a >> (j + k + 7)) & 1) && !((a >> (j + k + 1)) & 1)) << (j + k)); c += (a == b); } return c; } |
I extracted the following code from that output:
1 2 3 4 5 6 7 8 9 10 11 12 13 | #include <stdio.h> int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), b = a; for (int j = 9; j < 55; j += 8) for (int k = 1; k < 7; k++) b &= ~((((a >> (j + k)) & 1) && !((a >> (j + k - 9)) & 1) && !((a >> (j + k - 1)) & 1) && !((a >> (j + k + 7)) & 1) && !((a >> (j + k + 1)) & 1)) << (j + k)); c += (a == b); } return c; } |
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 | #include <stdio.h> int count() { int c = 0; for (int i = 0; i < 1<<16; i++) { unsigned long long a = ((i & 0xf) << 9) | ((i & 0xf0) << 13) | ((i & 0xf00) << 17) | ((i & 0xf000) << 21), b = a; for (int j = 9; j < 55; j += 8) for (int k = 1; k < 7; k++) b &= ~((((a >> (j + k)) & 1) && !((a >> (j + k - 9)) & 1) && !((a >> (j + k - 1)) & 1) && !((a >> (j + k + 7)) & 1) && !((a >> (j + k + 1)) & 1)) << (j + k)); c += (a == b); } return c; } #include<stdio.h> #include<stdlib.h> int main() { int answer = count(); int expected = 27488; if (answer != expected) { printf("Wrong answer; got %d instead of %d.\n", answer, expected); exit(1); } printf("All tests passed\n"); } |
Wrong answer; got 36880 instead of 27488.
Testing if the previous output contains the string All tests passed
: False
Resulting in output: False