this post was submitted on 04 Dec 2024
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Advent Of Code

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๐ŸŒš - 2024 DAY 4 SOLUTIONS - ๐ŸŒš (self.advent_of_code)
submitted 1 month ago by CameronDev to c/advent_of_code
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Day 4: Ceres Search

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[โ€“] [email protected] 1 points 1 month ago* (last edited 1 month ago)

Julia

Had some time to clean up the code today since the solution was quite straight forward after making a plan on how to approach it.

spoiler

function readWordSearch(inputFile::String)::Matrix{Char}
	f = open(inputFile,"r")
	lines::Vector{String} = readlines(f)
	close(f)
	wordSearch = Matrix{Char}(undef,length(lines),length(lines))
	for (i,line) in enumerate(lines)
		wordSearch[i,:] = collect(line)
	end
	return wordSearch
end

function countXMASAppearances(wS::Matrix{Char})::Int
	appearanceCount::Int = 0
	for i=1 : size(wS)[1] #lines
		for j=1 : size(wS)[2] #columns
			wS[i,j]!='X' ? continue : nothing #continue if char is not X
			#if char is X, check surrounding area
			# check horizontals
			#left
			j>=4 ? (wS[i,j-1]*wS[i,j-2]*wS[i,j-3]=="MAS" ? appearanceCount+=1 : nothing) : nothing
			#right
			j<=size(wS)[2]-3 ? (wS[i,j+1]*wS[i,j+2]*wS[i,j+3]=="MAS" ? appearanceCount+=1 : nothing) : nothing
			# check verticals
			#up
			i>=4 ? (wS[i-1,j]*wS[i-2,j]*wS[i-3,j]=="MAS" ? appearanceCount+=1 : nothing) : nothing
			#down
			i<=size(wS)[1]-3 ? (wS[i+1,j]*wS[i+2,j]*wS[i+3,j]=="MAS" ? appearanceCount+=1 : nothing) : nothing
			# check diagonals
			#left up
			i>=4 && j>=4 ? (wS[i-1,j-1]*wS[i-2,j-2]*wS[i-3,j-3]=="MAS" ? appearanceCount+=1 : nothing) : nothing
			#right up
			i>=4 && j<=size(wS)[2]-3 ? (wS[i-1,j+1]*wS[i-2,j+2]*wS[i-3,j+3]=="MAS" ? appearanceCount+=1 : nothing) : nothing
			#left down
			i<=size(wS)[1]-3 && j>=4 ? (wS[i+1,j-1]*wS[i+2,j-2]*wS[i+3,j-3]=="MAS" ? appearanceCount+=1 : nothing) : nothing
			#right down
			i<=size(wS)[1]-3 && j<=size(wS)[2]-3 ? (wS[i+1,j+1]*wS[i+2,j+2]*wS[i+3,j+3]=="MAS" ? appearanceCount+=1 : nothing) : nothing
		end
	end
	return appearanceCount
end

function countX_MASAppearances(wordSearch::Matrix{Char})::Int
	appearances::Int = 0
	for l=2 : size(wordSearch)[1]-1
		for c=2 : size(wordSearch)[2]-1
			wordSearch[l,c]!='A' ? continue : nothing
			checkArr = [wordSearch[l-1,c-1],wordSearch[l-1,c+1],wordSearch[l+1,c-1],wordSearch[l+1,c+1]]
			if checkArr in [['M','M','S','S'],['M','S','M','S'],['S','S','M','M'],['S','M','S','M']]
				appearances += 1
			end
		end
	end
	return appearances
end

wordSearch::Matrix{Char} = readWordSearch(inputFile
prinltn("part 1 appearances: $(countXMASAppearances(wordSearch))")
prinltn("part 2 appearances: $(countX_MASAppearances(wordSearch))")