Day Thirteen (Nim)

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diff --git a/2022/nim/day13/src/main.nim b/2022/nim/day13/src/main.nim
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+# Day 13: Distress Signal
+import std/[os, strutils, sequtils, sugar, algorithm]
+
+let input = paramStr(1).readFile().strip().split("\n\n").mapIt(it.split("\n"))
+
+type Kleenean {.pure.} = enum
+  False = -1,
+  Maybe = 0,
+  True = 1
+
+func partition(chunk: string): seq[string] =
+  var depth = 0
+  if chunk == "[]":
+    return @[]
+  if chunk.len == 0 or chunk[0] != '[':
+    return @[chunk]
+  result.add("")
+  for c in chunk[1 ..< chunk.len-1]:
+    if c == '[':
+      depth += 1
+    if c == ']':
+      depth -= 1
+    if c == ',' and depth == 0:
+      result.add("")
+    else:
+      result[result.len - 1] &= c
+
+func compare(a, b: string): Kleenean =
+  let (a, b) = (a.partition(), b.partition())
+  for (left, right) in zip(a, b):
+    if left.contains("[") or right.contains("["):
+      let value = compare(left, right)
+      if value == Maybe:
+        continue
+      else:
+        return value
+    if parseInt(left) < parseInt(right):
+      return True
+    elif parseInt(left) > parseInt(right):
+      return False
+  if a.len < b.len:
+    return True
+  elif a.len > b.len:
+    return False
+  else:
+    return Maybe
+
+var sum = 0
+for i, group in input:
+  let value = compare(group[0], group[1])
+  if value == True:
+    sum += i+1
+echo sum
+
+var key = 1
+for i, line in input.concat()
+  .concat(@["[[2]]", "[[6]]"])
+    .sorted((x, y) => (compare(x, y).ord), Descending):
+  if line == "[[2]]" or line == "[[6]]":
+    key *= i+1
+echo key