Day 25: Code Chronicle

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

  • @[email protected]
    link
    fedilink
    52 days ago

    C

    Merry Christmas everyone!

    Code
    #include "common.h"
    
    int
    main(int argc, char **argv)
    {
    	static char buf[7];
    	static short h[500][5];	/* heights */
    	static short iskey[500];
    	int p1=0, nh=0, i,j,k;
    
    	if (argc > 1)
    		DISCARD(freopen(argv[1], "r", stdin));
    	
    	for (nh=0; !feof(stdin) && !ferror(stdin); nh++) {
    		assert(nh < (int)LEN(h));
    
    		for (i=0; i<7; i++) {
    			fgets(buf, 7, stdin);
    			if (i==0)
    				iskey[nh] = buf[0] == '#';
    			for (j=0; j<5; j++)
    				h[nh][j] += buf[j] == '#';
    		}
    
    		/* skip empty line */
    		fgets(buf, 7, stdin);
    	}
    
    	for (i=0; i<nh; i++)
    	for (j=0; j<nh; j++)
    		if (iskey[i] && !iskey[j]) {
    			for (k=0; k<5 && h[i][k] + h[j][k] <= 7; k++) ;
    			p1 += k == 5;
    		}
    
    	printf("25: %d\n", p1);
    	return 0;
    }
    

    https://codeberg.org/sjmulder/aoc/src/branch/master/2024/c/day25.c

    Made the 1 second challenge with most of it to spare! 😎

    $ time bmake bench                                                                                                      
    day01  0:00.00  1912 Kb  0+88 faults                                                                                            
    day02  0:00.00  1992 Kb  0+91 faults 
    day03  0:00.00  1920 Kb  0+93 faults
    day04  0:00.00  1912 Kb  0+90 faults 
    day05  0:00.00  2156 Kb  0+91 faults
    day06  0:00.03  1972 Kb  0+100 faults
    day07  0:00.06  1892 Kb  0+89 faults
    day08  0:00.00  1772 Kb  0+87 faults 
    day09  0:00.02  2024 Kb  0+137 faults
    day10  0:00.00  1876 Kb  0+87 faults 
    day11  0:00.00  6924 Kb  0+3412 faults
    day12  0:00.00  1952 Kb  0+103 faults
    day13  0:00.00  1908 Kb  0+88 faults
    day14  0:00.05  1944 Kb  0+92 faults                                                                                            
    day15  0:00.00  2040 Kb  0+89 faults
    day16  0:00.03  2020 Kb  0+250 faults
    day17  0:00.00  1896 Kb  0+88 faults
    day18  0:00.00  1952 Kb  0+107 faults
    day19  0:00.01  1904 Kb  0+91 faults
    day20  0:00.01  2672 Kb  0+325 faults
    day21  0:00.00  1804 Kb  0+86 faults
    day22  0:00.03  2528 Kb  0+371 faults
    day23  0:00.02  2064 Kb  0+152 faults
    day24  0:00.00  1844 Kb  0+89 faults
    day25  0:00.00  1788 Kb  0+89 faults  
                                                                    
    real    0m0,359s