Day 4: Scratchcards


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)
  • Code block support is not fully rolled out yet but likely will be in the middle of the event. Try to share solutions as both code blocks and using something such as https://topaz.github.io/paste/ or pastebin (code blocks to future proof it for when 0.19 comes out and since code blocks currently function in some apps and some instances as well if they are running a 0.19 beta)

FAQ


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  • sjmulder@lemmy.sdf.org
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    11 months ago

    Language: C

    Another day of parsing, another day of strsep() to the rescue. Today was one of those satisfying days where the puzzle text is complicated but the solution is simple once well understood.

    GitHub link

    Code (29 lines)
    int main()
    {
    	char line[128], *rest, *tok;
    	int nextra[200]={0}, nums[10], nnums;
    	int p1=0,p2=0, id,val,nmatch, i;
    
    	for (id=0; (rest = fgets(line, sizeof(line), stdin)); id++) {
    		nnums = nmatch = 0;
    
    		while ((tok = strsep(&rest, " ")) && !strchr(tok, ':'))
    			;
    		while ((tok = strsep(&rest, " ")) && !strchr(tok, '|'))
    			if ((val = atoi(tok)))
    				nums[nnums++] = val;
    		while ((tok = strsep(&rest, " ")))
    			if ((val = atoi(tok)))
    				for (i=0; i<nnums; i++)
    					nmatch += nums[i] == val;
    
    		for (i=0; i<nmatch; i++)
    			nextra[id+1+i] += nextra[id]+1;
    
    		p1 += nmatch ? 1 << (nmatch-1) : 0;
    		p2 += nextra[id]+1;
    	}
    
    	printf("%d %d\n", p1, p2);
    	return 0;
    }
    

        • mykl@lemmy.world
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          11 months ago

          Ohh that’s interesting, I’ve seen a few comments about mishandling of special chars in code blocks and assumed it was a server issue, maybe it’s fixed in newer releases or perhaps it’s client side.