Day 4: Printing Department
Megathread guidelines
- Keep top level comments as only solutions, if you want to say something other than a solution put it in a new post. (replies to comments can be whatever)
- You can send code in code blocks by using three backticks, the code, and then three backticks or use something such as https://topaz.github.io/paste/ if you prefer sending it through a URL
FAQ
- What is this?: Here is a post with a large amount of details: https://programming.dev/post/6637268
- Where do I participate?: https://adventofcode.com/
- Is there a leaderboard for the community?: We have a programming.dev leaderboard with the info on how to join in this post: https://programming.dev/post/6631465


C
For loops!
Code
#include <stdio.h> #define GZ 144 static char g[GZ][GZ]; int main() { int p1=0,p2=0, nc=0, x,y; for (y=1; fgets(g[y]+1, GZ-2, stdin); y++) ; for (y=1; y<GZ-1; y++) for (x=1; x<GZ-1; x++) p1 += g[y][x] == '@' && (g[y-1][x-1] == '@') + (g[y-1][x ] == '@') + (g[y-1][x+1] == '@') + (g[y ][x-1] == '@') + (g[y ][x+1] == '@') + (g[y+1][x-1] == '@') + (g[y+1][x ] == '@') + (g[y+1][x+1] == '@') < 4; do { nc = 0; for (y=1; y<GZ-1; y++) for (x=1; x<GZ-1; x++) if (g[y][x] == '@' && (g[y-1][x-1] == '@') + (g[y-1][x ] == '@') + (g[y-1][x+1] == '@') + (g[y ][x-1] == '@') + (g[y ][x+1] == '@') + (g[y+1][x-1] == '@') + (g[y+1][x ] == '@') + (g[y+1][x+1] == '@') < 4) { nc++; p2++; g[y][x] = '.'; } } while (nc); printf("04: %d %d\n", p1, p2); return 0; }Repo
For my x86-16 version, the 20K input is pushing it over the 64K .COM limit, so I’ll need to implement some better compression first.