2023 Day 2

2023/day02.nim

@@ -0,0 +1,61 @@
+import std/strscans
+import std/strutils
+
+proc part1(): int =
+  let f = open("input/day02.txt")
+  defer: f.close()
+
+  let
+    reds = 12
+    greens = 13
+    blues = 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
+
+proc part2(): int =
+  let f = open("input/day02.txt")
+  defer: f.close()
+
+  var line: string
+  while f.readLine(line):
+    var id: int
+    var rest: string
+
+    if not scanf(line, "Game $i: $*$.", id, rest):
+      echo "ERROR"
+      continue
+
+    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
+    inc result, power
+
+echo part1()
+echo part2()