1 files changed, 77 insertions, 2 deletions
diff --git a/aoc2017-gleam/src/aoc_2017/day_14.gleam b/aoc2017-gleam/src/aoc_2017/day_14.gleam
index a0a1145..cd60a74 100644
--- a/aoc2017-gleam/src/aoc_2017/day_14.gleam
+++ b/aoc2017-gleam/src/aoc_2017/day_14.gleam
@@ -1,7 +1,82 @@
+import aoc_2017/day_10.{pt_2 as knot}
+import gleam/int
+import gleam/list
+import gleam/result
+import gleam/set
+import gleam/string
+import helpers/state
+
 pub fn pt_1(input: String) {
-  todo as "part 1 not implemented"
+  use acc, row <- list.fold(make_rows(input), 0)
+  let count = row |> knot() |> popcount()
+  acc + count
+}
+
+fn make_rows(input: String) {
+  use row <- list.map(list.range(0, 127))
+  input <> "-" <> int.to_string(row)
+}
+
+fn popcount(hex_number: String) -> Int {
+  let assert Ok(n) = int.base_parse(hex_number, 16)
+  let assert Ok(digits) = int.digits(n, 2)
+
+  use acc, digit <- list.fold(digits, 0)
+  case digit {
+    1 -> acc + 1
+    _ -> acc
+  }
 }
 
 pub fn pt_2(input: String) {
-  todo as "part 2 not implemented"
+  let grid = state.start_actor(make_grid(input))
+
+  find_next_group(grid, 0)
+}
+
+fn make_grid(input: String) {
+  let raw_grid =
+    list.map(make_rows(input), fn(row) {
+      row
+      |> knot()
+      |> int.base_parse(16)
+      |> result.map(int.to_base2)
+      |> result.map(string.pad_left(_, with: "0", to: 128))
+      |> result.map(string.to_graphemes)
+    })
+    |> result.values
+
+  {
+    use total_acc, row, i <- list.index_fold(raw_grid, set.new())
+    use acc, bit, j <- list.index_fold(row, total_acc)
+    case bit {
+      "1" -> set.insert(acc, #(i, j))
+      _zero -> acc
+    }
+  }
+}
+
+fn find_next_group(actor, count) {
+  case state.pop(actor) {
+    Ok(p) -> {
+      list.each(neighbors(p), remove_neighbor(actor, _))
+      find_next_group(actor, count + 1)
+    }
+    Error(Nil) -> count
+  }
+}
+
+fn neighbors(of: #(Int, Int)) {
+  let #(i, j) = of
+  [#(i + 1, j), #(i - 1, j), #(i, j + 1), #(i, j - 1)]
+}
+
+fn remove_neighbor(actor, point) {
+  case state.check(actor, point) {
+    True -> {
+      state.drop(actor, point)
+      list.each(neighbors(point), remove_neighbor(actor, _))
+    }
+    False -> Nil
+  }
 }