LeetcodeTextJustification1.scala

  def buildLine(words: Vector[String], maxWidth: Int, wordsWidth: Int): String = {
    val spacePlacements = words.size - 1
    val missingSpaces = maxWidth - wordsWidth
    val numSpace = missingSpaces / Math.max(spacePlacements, 1)
    val remSpaces = missingSpaces % Math.max(spacePlacements, 1)

    words.zipWithIndex.foldLeft(new StringBuffer()) { case (buf, (word, pos)) =>
      buf.append(word)
      if (pos == 0 || pos < words.size - 1) { // first or not last
        buf.append(Array.fill(numSpace + (if (pos < remSpaces) 1 else 0))(' '))
      } else {
        buf
      }
    }.toString
  }