my aoc solutions
day 7 pt 2
+53
-3
+53
-3
src/aoc_2025/day_7.gleam
+53
-3
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/option.{None, Some}
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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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pub fn parse(input: String) -> List(List(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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}
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pub fn pt_1(input: List(List(String))) {
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input
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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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···
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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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pub fn pt_2(input: List(List(String))) {
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input
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|> list.fold(dict.new(), fn(columns_with_beam, row) {
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let columns_with_beam =
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list.index_fold(
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row,
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columns_with_beam,
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fn(columns_with_beam, item, column) {
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case item {
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"S" -> columns_with_beam |> dict.upsert(column, add(_, 1))
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"^" -> {
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case dict.get(columns_with_beam, column) {
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Ok(count) if count > 0 -> {
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// echo count
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let columns_with_beam =
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columns_with_beam
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|> dict.delete(column)
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|> dict.upsert(column - 1, add(_, count))
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|> dict.upsert(column + 1, add(_, count))
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columns_with_beam
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}
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_ -> columns_with_beam
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}
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}
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// "."
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_ -> columns_with_beam
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}
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},
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)
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columns_with_beam
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})
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|> dict.fold(0, fn(acc, _key, value) { acc + value })
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}
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+
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fn add(item: option.Option(Int), amount) -> Int {
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let amount = case item {
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Some(count) -> count + amount
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None -> amount
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}
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case amount {
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amount if amount < 0 -> 0
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_ -> amount
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}
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}