LeetcodeTextJustification2.scala

  def justify(words: Array[String], maxWidth: Int): Vector[String] = {
    val (lines, lastWords, width) = words.foldLeft((Vector.empty[String], Vector.empty[String], 0)) {
      case ((resultLines, wordAcc, currentLineLen), word) =>
        if ((currentLineLen + word.length + (wordAcc.size - 1)) < maxWidth) {
          (resultLines, wordAcc :+ word, currentLineLen + word.length)
        } else {
          val line = buildLine(wordAcc, maxWidth, currentLineLen)
          (resultLines :+ line, Vector(word), word.length)
        }
    }
    val lastLine = buildLine(lastWords, width + (lastWords.size - 1), width).padTo(maxWidth, ' ')
    (lines :+ lastLine)
  }