refactor: 2023 Day 2

2023/day02.nim

@@ -1,34 +1,49 @@
 import std/strscans
 import std/strutils
 
+type Turn = object
+  r, g, b: int
+
+func parseTurn(text: string): Turn =
+  for count in text.split(","):
+    let parts = count.strip.split()
+    case parts[1]:
+      of "red": (result.r = parts[0].parseInt)
+      of "green": (result.g = parts[0].parseInt)
+      of "blue": (result.b = parts[0].parseInt)
+
+
+type Game = object
+  id: int
+  turns: seq[Turn]
+
+func parseGame(line: string): Game =
+  var rest: string
+
+  if not scanf(line, "Game $i: $*$.", result.id, rest):
+    raise newException(ValueError, line)
+
+  for turn in rest.split(";"):
+    result.turns.add(parseTurn(turn))
+
+type Bag = object
+  r, g, b: int
+
 proc part1(): int =
   let f = open("input/day02.txt")
   defer: f.close()
 
-  let
-    reds = 12
-    greens = 13
-    blues = 14
+  let bag = Bag(r: 12, g: 13, b: 14)
 
   var line: string
   while f.readLine(line):
-    var id: int
-    var rest: string
-
-    block game:
-      if not scanf(line, "Game $i: $*$.", id, rest):
-        echo "ERROR"
-        continue
-
-      for counts in rest.split(";"):
-        var r, g, b: int
-        for s in counts.split(","):
-          let parts = s.strip.split()
-          case parts[1]:
-            of "red": (if parts[0].parseInt > reds: break game)
-            of "green": (if parts[0].parseInt > greens: break game)
-            of "blue": (if parts[0].parseInt > blues: break game)
-      inc result, id
+    block current:
+      let game = parseGame(line)
+      for turn in game.turns:
+        if turn.r > bag.r: break current
+        if turn.g > bag.g: break current
+        if turn.b > bag.b: break current
+      inc result, game.id
 
 proc part2(): int =
   let f = open("input/day02.txt")
@@ -36,25 +51,15 @@ proc part2(): int =
 
   var line: string
   while f.readLine(line):
-    var id: int
-    var rest: string
+    var bag: Bag
 
-    if not scanf(line, "Game $i: $*$.", id, rest):
-      echo "ERROR"
-      continue
+    let game = parseGame(line)
+    for turn in game.turns:
+      bag.r = max(bag.r, turn.r)
+      bag.g = max(bag.g, turn.g)
+      bag.b = max(bag.b, turn.b)
 
-    var reds, greens, blues: int
-
-    for counts in rest.split(";"):
-      var r, g, b: int
-      for s in counts.split(","):
-        let parts = s.strip.split()
-        case parts[1]:
-          of "red": (reds = max(reds, parts[0].parseInt))
-          of "green": (greens = max(greens, parts[0].parseInt))
-          of "blue": (blues = max(blues, parts[0].parseInt))
-
-    let power = reds * greens * blues
+    let power = bag.r * bag.g * bag.b
     inc result, power
 
 echo part1()