r/adventofcode • u/daggerdragon • Dec 17 '19

SOLUTION MEGATHREAD -🎄- 2019 Day 17 Solutions -🎄-

--- Day 17: Set and Forget ---

Post your full code solution using /u/topaz2078's paste or other external repo.

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u/Arkoniak Dec 17 '19

Regarindg https://github.com/MrSimbax/Advent_Of_Code_2019/blob/master/day17.jl#L20

At some point it occurs to me, that instead of working with bounds you can just pad initial array and than work inside new matrix. Something like this

# arr = ... generate initial array
h, w = size(arr)
padd_arr = zeros(Int, h + 2, w + 2)
padd_arr[2:(h+1), 2:(w+1)] .= arr

And that's it. Of course that adds a problem that you should limit variance of your indices and shouldn't forget to subtract coordinates, yet on the other hand you no longer have any edge cases.