printTable.scala

          def printTable[A](rows: Seq[A], header: String*)(f: A => Seq[String]) = {
            val rowsStrings = rows.map(f)
            val cells       = header +: rowsStrings
            val widths      = cells.transpose.map(_.map(_.length).max)
            val format      = widths.map("%-" + _ + "s").mkString(" | ")
            val headerStr   = format.format(header *)
            val separator   = widths.map("-" * _).mkString("-+-", "-+-", "-")
            val rowsStr     = rowsStrings.map(format.format(_ *)).mkString("\n")
            println(s"$headerStr\n$separator\n$rowsStr")
          }