[aoc/2022] Finish day 3

2 files changed, 35 insertions, 0 deletions

diff --git a/aoc/2022/03/part-one.nim b/aoc/2022/03/part-one.nim
new file mode 100644
index 0000000..0f16754
--- /dev/null
+++ b/aoc/2022/03/part-one.nim
@@ -0,0 +1,19 @@
+import math
+import sequtils
+import sets
+import strutils
+
+func priority(item: int): int =
+  result = item - 96
+  if result < 0:
+    result += 58
+
+func examine(sack: string): int =
+  let
+    size = sack.len div 2
+    other = to_hash_set sack[0 ..< size]
+  for c in sack[size .. ^1]:
+    if c in other:
+      return priority ord c
+
+echo sum stdin.read_all.strip.split_lines.map examine
diff --git a/aoc/2022/03/part-two.nim b/aoc/2022/03/part-two.nim
new file mode 100644
index 0000000..ef27011
--- /dev/null
+++ b/aoc/2022/03/part-two.nim
@@ -0,0 +1,16 @@
+import math
+import sequtils
+import sets
+import strutils
+
+func priority(group: seq[string]): int =
+  let sets = group.map_it it.to_hash_set
+  var common = sets.foldl a * b
+  result = common.pop.ord - 96
+  if result < 0:
+    result += 58
+
+let
+  elves = split_lines strip read_all stdin
+  groups = elves.distribute elves.len div 3
+echo sum groups.map priority