Day 6

day_06/solve.nim

@@ -0,0 +1,24 @@
+import std/[sequtils]
+
+const input = readFile("day_06/input.txt")
+
+proc isMarker(segment: string): bool {.inline.} =
+  segment.deduplicate == segment
+
+proc findMarkerIndex(data: string, markerSize: int): int =
+  let offset = markerSize - 1
+  for i in offset..input.len-1:
+    if input[i-offset..i].isMarker:
+      return i
+
+# How many characters need to be processed before the first start-of-packet marker is detected?
+proc solvePart1() =
+  echo "Marker: " & $(input.findMarkerIndex(4) + 1)
+
+# How many characters need to be processed before the first start-of-message marker is detected?
+proc solvePart2() =
+  echo "Marker: " & $(input.findMarkerIndex(14) + 1)
+
+if isMainModule:
+  solvePart1()
+  solvePart2()