object MainObject {

  def main(args: Array[String]): Unit = {
    println("Please write a number and number lines")
    val inputLines = readInt
    var lines : List[String] = List()
    for(i <- 0 until inputLines){
        lines = lines :+ readLine().toString()
    }
    
    val chars = lines.map( _.toList ).toSeq
    consume(chars)
     
    
  }
  
  def consume(lines: Seq[List[Char]]) : Unit = {
     lines.foreach(
     		l =>
     			print(l.headOption.map( _.toString ).getOrElse(" "))
     )
     println()
     if (lines.filter( _.length > 0 ).nonEmpty) consume( lines.map( _.drop(1) ) )
  }

}