object day03 {
  def main(args: Array[String]): Unit = {
    val numbers = io.Source.stdin
      .getLines()
      .map(ln => ln.chars.map(_ - '0').toArray)
      .toArray

    var occurences = Array.fill(numbers(0).length)(0)
    for (number <- numbers) {
      for ((bit, i) <- number.zipWithIndex)
        occurences(i) += bit
    }

    var gamma = 0
    var epsilon = 0
    for ((freq, i) <- occurences.zipWithIndex) {
      val shifted = 1 << occurences.length - 1 >> i
      if (freq > (numbers.length / 2))
        gamma |= shifted
      else
        epsilon |= shifted
    }

    val part1 = gamma * epsilon
    println(s"part1: $part1")
  }
}