nuv.sh
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src/aoc_2025/day_7.gleam
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src/aoc_2025/day_7.gleam
···
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import gleam/dict
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import gleam/list
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import gleam/pair
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import gleam/set
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import gleam/string
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pub fn pt_1(input: String) {
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input
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// rows
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|> string.split("\n")
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// rows as chars
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|> list.map(string.to_graphemes)
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|> list.fold(#(0, set.new()), fn(acc, row) {
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let #(split_sum, columns_with_beam) = acc
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let #(splits, columns_with_beam) =
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list.index_fold(row, #(0, columns_with_beam), fn(acc, item, column) {
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let #(split_sum, columns_with_beam) = acc
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case item {
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"S" | "|" -> #(split_sum, set.insert(columns_with_beam, column))
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"^" -> {
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case columns_with_beam |> set.contains(column) {
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True -> {
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let columns_with_beam =
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columns_with_beam
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|> set.delete(column)
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|> set.insert(column - 1)
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|> set.insert(column + 1)
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#(split_sum + 1, columns_with_beam)
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}
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False -> #(split_sum, columns_with_beam)
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}
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}
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// "."
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_ -> acc
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}
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})
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#(split_sum + splits, columns_with_beam)
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})
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|> pair.first()
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}
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pub fn pt_2(input: String) {
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todo as "part 2 not implemented"
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}