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; } |
Let me help golf this code: 1. **What the function does**: It counts how many 16-bit numbers, when arranged in an 8x8 grid, remain unchanged after applying this rule: any 1 that has no adjacent 1s (top, left, bottom, right) becomes 0. 2. **Ways to make it shorter**: - Remove redundant calculations of bit positions - Combine the nested loops - Use bitwise operations more efficiently - Remove temporary variables where possible - Use smaller integer types where possible - Simplify the position calculations 3. **Short version**:
1 | int count(){int c=0,i,j,n;for(n=0;n<65536;n++){long long a=((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21),b=a;for(i=8;i<56;i++)if((a>>i)&1&&!((b>>(i-8)&1)|(b>>(i-1)&1)|(b>>(i+1)&1)|(b>>(i+8)&1)))a^=1LL<<i;c+=a==b;}return c;} |
1 | int count(){int c=0,n,i;for(n=0;n<65536;n++){long long a=((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);for(i=8;i<56;i++)a^=((a>>i)&1&&!((a>>(i-8)|(a>>(i-1)|(a>>(i+1)|(a>>(i+8))))&1))<<i;c+=a==((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);}return c;} |
I extracted the following code from that output:
1 | int count(){int c=0,n,i;for(n=0;n<65536;n++){long long a=((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);for(i=8;i<56;i++)a^=((a>>i)&1&&!((a>>(i-8)|(a>>(i-1)|(a>>(i+1)|(a>>(i+8))))&1))<<i;c+=a==((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);}return c;} |
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | int count(){int c=0,n,i;for(n=0;n<65536;n++){long long a=((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);for(i=8;i<56;i++)a^=((a>>i)&1&&!((a>>(i-8)|(a>>(i-1)|(a>>(i+1)|(a>>(i+8))))&1))<<i;c+=a==((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);}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"); } |
main.c: In function 'count':
main.c:2:201: error: expected ')' before ';' token
2 | int count(){int c=0,n,i;for(n=0;n<65536;n++){long long a=((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);for(i=8;i<56;i++)a^=((a>>i)&1&&!((a>>(i-8)|(a>>(i-1)|(a>>(i+1)|(a>>(i+8))))&1))<<i;c+=a==((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);}return c;}
| ~ ^
| )
main.c:2:269: error: expected ';' before '}' token
2 | int count(){int c=0,n,i;for(n=0;n<65536;n++){long long a=((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);for(i=8;i<56;i++)a^=((a>>i)&1&&!((a>>(i-8)|(a>>(i-1)|(a>>(i+1)|(a>>(i+8))))&1))<<i;c+=a==((n&15L)<<9)|((n&240L)<<13)|((n&3840L)<<17)|((n&61440L)<<21);}return c;}
| ^
| ;
main.sh: line 2: ./a.out: No such file or directory
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; } |
Let me help golf this code: 1. **Function Explanation:** The function counts how many 16-bit numbers, when mapped to an 8x8 grid pattern, remain unchanged after applying this rule: any 1 that has no adjacent 1s (top, bottom, left, right) becomes 0. 2. **Ways to make it shorter:** - Remove the separate ROWS/COLS variables since they're always 8 - Combine the bit operations in the initial array creation - Remove temporary variables where possible - Use bitwise operations instead of individual neighbor checks - Combine loops where possible - Remove unnecessary type specifications 3. **Short version:**
1 | int count(){int c=0,i;for(i=0;i<65536;i++){unsigned long long a=((long long)i<<9)&0x8080808080808080;c+=!((a^a>>1|a^a<<1|a^a>>8|a^a<<8)&a);}return c;} |
1 | int count(void){int c=0,i;for(i=0;i<1<<16;i++)c+=!(((long long)i<<9&0x8080808080808080)&((long long)i<<10|i<<8|(long long)i<<17|i<<1)<<9&0x8080808080808080);return c;} |
I extracted the following code from that output:
1 | int count(void){int c=0,i;for(i=0;i<1<<16;i++)c+=!(((long long)i<<9&0x8080808080808080)&((long long)i<<10|i<<8|(long long)i<<17|i<<1)<<9&0x8080808080808080);return c;} |
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | int count(void){int c=0,i;for(i=0;i<1<<16;i++)c+=!(((long long)i<<9&0x8080808080808080)&((long long)i<<10|i<<8|(long long)i<<17|i<<1)<<9&0x8080808080808080);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 28672 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; } |
Let me help golf this code: 1. **What the function does:** - It counts how many 16-bit numbers, when arranged in an 8x8 grid, remain unchanged after applying this rule: - A cell with value 1 becomes 0 if all its adjacent cells (top, right, bottom, left) are 0 - Only inner cells (not on edges) are checked - Returns count of numbers that don't change 2. **Ways to make it shorter:** - Use bitwise operations instead of loops for neighbor checking - Pre-calculate bit masks for position checks - Remove unnecessary variables - Use shorter variable names - Combine operations 3. **Short version attempt:**
1 2 3 4 5 6 7 | int count(){ int c=0,i; for(i=0;i<65536;i++){ unsigned long long a=((i&15L)<<9)|((i&240L)<<13)|((i&3840L)<<17)|((i&61440L)<<21),t=a; for(int p=9;p<55;p++)if(p%8>0&&p%8<7&&((t>>p)&1)&&!((t>>(p-8)&1)|(t>>(p-1)&1)|(t>>(p+1)&1)|(t>>(p+8)&1)))a&=~(1ULL<<p); c+=t==a;} return c;} |
1 | int count(){int c=0,i;for(i=0;i<65536;i++){unsigned long long a=((i&15L)<<9)|((i&240L)<<13)|((i&3840L)<<17)|((i&61440L)<<21),t=a;for(int p=9;p<55;p++)p%8>0&&p%8<7&&((t>>p)&1)&&!((t>>(p-8)|t>>(p-1)|t>>(p+1)|t>>(p+8))&1)&&(a&=~(1ULL<<p));c+=t==a;}return c;} |
I extracted the following code from that output:
1 2 3 4 5 6 7 | int count(){ int c=0,i; for(i=0;i<65536;i++){ unsigned long long a=((i&15L)<<9)|((i&240L)<<13)|((i&3840L)<<17)|((i&61440L)<<21),t=a; for(int p=9;p<55;p++)if(p%8>0&&p%8<7&&((t>>p)&1)&&!((t>>(p-8)&1)|(t>>(p-1)&1)|(t>>(p+1)&1)|(t>>(p+8)&1)))a&=~(1ULL<<p); c+=t==a;} 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 | int count(){ int c=0,i; for(i=0;i<65536;i++){ unsigned long long a=((i&15L)<<9)|((i&240L)<<13)|((i&3840L)<<17)|((i&61440L)<<21),t=a; for(int p=9;p<55;p++)if(p%8>0&&p%8<7&&((t>>p)&1)&&!((t>>(p-8)&1)|(t>>(p-1)&1)|(t>>(p+1)&1)|(t>>(p+8)&1)))a&=~(1ULL<<p); c+=t==a;} 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 22946 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; } |
Let me help golf this code: 1. **Function Explanation:** This function counts how many 16-bit numbers create a stable 8x8 grid pattern where a cell stays '1' only if it has at least one neighboring '1' in cardinal directions (up, down, left, right). It spreads these 16 bits into a 64-bit grid and checks if the pattern remains unchanged after applying the rules. 2. **Ways to make it shorter:** - Remove separate ROWS/COLS variables since they're always 8 - Combine the nested loops into position calculations - Use bitwise operations instead of individual neighbor checks - Remove temporary variables where possible - Use shorter integer types where possible 3. **Shortened version:**
1 | int count(){int c=0,i;for(i=0;i<65536;i++){unsigned long long a=((i&15ULL)<<9)|((i&240ULL)<<13)|((i&3840ULL)<<17)|((i&61440ULL)<<21),t=a;for(int p=9;p<55;p++)if(p%8>0&&p%8<7&&((t>>p)&1)&&!((t>>(p-8)&1)|(t>>(p-1)&1)|(t>>(p+1)&1)|(t>>(p+8)&1)))a&=~(1ULL<<p);c+=t==a;}return c;} |
1 | int count(){int c=0,i;for(i=0;i<1<<16;i++){unsigned long long a=((i&15ULL)<<9)|((i&240ULL)<<13)|((i&3840ULL)<<17)|((i&61440ULL)<<21);for(int p=9;p<55;p++)p%8&&p%8<7&&(a>>p&1)&&!(a>>(p-8)|a>>(p-1)|a>>(p+1)|a>>(p+8)&1)&&(a&=~(1ULL<<p));c+=a==((i&15ULL)<<9)|((i&240ULL)<<13)|((i&3840ULL)<<17)|((i&61440ULL)<<21);}return c;} |
I extracted the following code from that output:
1 | int count(){int c=0,i;for(i=0;i<1<<16;i++){unsigned long long a=((i&15ULL)<<9)|((i&240ULL)<<13)|((i&3840ULL)<<17)|((i&61440ULL)<<21);for(int p=9;p<55;p++)p%8&&p%8<7&&(a>>p&1)&&!(a>>(p-8)|a>>(p-1)|a>>(p+1)|a>>(p+8)&1)&&(a&=~(1ULL<<p));c+=a==((i&15ULL)<<9)|((i&240ULL)<<13)|((i&3840ULL)<<17)|((i&61440ULL)<<21);}return c;} |
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | int count(){int c=0,i;for(i=0;i<1<<16;i++){unsigned long long a=((i&15ULL)<<9)|((i&240ULL)<<13)|((i&3840ULL)<<17)|((i&61440ULL)<<21);for(int p=9;p<55;p++)p%8&&p%8<7&&(a>>p&1)&&!(a>>(p-8)|a>>(p-1)|a>>(p+1)|a>>(p+8)&1)&&(a&=~(1ULL<<p));c+=a==((i&15ULL)<<9)|((i&240ULL)<<13)|((i&3840ULL)<<17)|((i&61440ULL)<<21);}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 16 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; } |
Let me help golf this code: 1. Function Explanation: - It iterates through 16-bit numbers (0 to 2^16-1) - Each number is expanded into a 64-bit grid representation - It checks cells in a 8x8 grid - For each cell (except edges), if it's 1 and all adjacent cells are 0, it becomes 0 - Counts cases where no changes occurred 2. Optimization Ideas: - Remove ROWS/COLS constants - Combine position calculations - Remove temporary variables - Use bitwise operations more efficiently - Reduce loop nesting - Simplify neighbor checking 3. Short Version:
1 | int count(){int c=0,i,j,p;for(i=0;i<65536;i++){unsigned long long a=((i&15L)<<9)|((i&240L)<<13)|((i&3840L)<<17)|((i&61440L)<<21),t=a;for(p=9;p<55;p++)if(p%8&&p%8<7&&(t>>p&1)&&!((t>>(p-8)&1)|(t>>(p-1)&1)|(t>>(p+1)&1)|(t>>(p+8)&1)))a&=~(1ULL<<p);c+=t==a;}return c;} |
1 | int count(){int c=0,i;for(i=0;i<65536;i++){unsigned long long t=((i&15L)<<9)|((i&240L)<<13)|((i&3840L)<<17)|((i&61440L)<<21),a=t,p=8;while(++p<55)if(p%8&&p%8<7&&(t>>p&1)&&!((t>>(p-8)|t>>(p-1)|t>>(p+1)|t>>(p+8))&1))a^=1ULL<<p;c+=t==a;}return c;} |
I extracted the following code from that output:
1 | int count(){int c=0,i;for(i=0;i<65536;i++){unsigned long long t=((i&15L)<<9)|((i&240L)<<13)|((i&3840L)<<17)|((i&61440L)<<21),a=t,p=8;while(++p<55)if(p%8&&p%8<7&&(t>>p&1)&&!((t>>(p-8)|t>>(p-1)|t>>(p+1)|t>>(p+8))&1))a^=1ULL<<p;c+=t==a;}return c;} |
Running the following program:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | int count(){int c=0,i;for(i=0;i<65536;i++){unsigned long long t=((i&15L)<<9)|((i&240L)<<13)|((i&3840L)<<17)|((i&61440L)<<21),a=t,p=8;while(++p<55)if(p%8&&p%8<7&&(t>>p&1)&&!((t>>(p-8)|t>>(p-1)|t>>(p+1)|t>>(p+8))&1))a^=1ULL<<p;c+=t==a;}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 22946 instead of 27488.
Testing if the previous output contains the string All tests passed
: False
Resulting in output: True