aoc_2022_06_part1.nim

import std/[os,setutils]

const
  markerLen = 4

let datastream = readFile(paramStr(1))

for i in 0 .. (high(datastream) - markerLen):
  let chunk = datastream[i ..< i + markerLen]
  if chunk.toSet.card == markerLen:
    echo i + markerLen
    break