It took about 2 hours work to get the Haskell code ported and the resulting code runs in 3.5 seconds, a pretty good speed up. I haven't spent time trying to optimize either.
https://github.com/justinhj/advent-of-haskell/blob/cc53137bfc071d1d30bee2ce1e7e70d138bdf6ec/ZigDaySix/src/main.zig#L255
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https://github.com/justinhj/advent-of-haskell/blob/cc53137bfc071d1d30bee2ce1e7e70d138bdf6ec/ZigDaySix/src/main.zig#L255
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Comments
There is no Set in the stdlib, but maybe it's easy to find a community implementation, this was day 1 of Zig for me so I don't know.
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