Zhihu37118044.scala

object Zhihu37118044 {

  def printDeep(vector: IndexedSeq[_]) {
    import scalaz.std.indexedSeq._
    import scalaz.syntax.traverse._

    ((0 until 100):IxSq[Int]).foldLeftM[IxSq, Any](vector) {
      case (vector: IxSq[Any], _) =>
        vector
      case (value: Any , _) =>
        println(value)
        Vector.empty
    }
  }


  def main(arguments: Array[String]): Unit = {
    printDeep(
      Vector(
        Vector(
          Vector(
            Vector("000"), Vector("001")
          ),
          Vector(
            Vector("010"), Vector("011")
          )
        ),
        Vector(
          Vector(
            Vector("100"), Vector("101")
          ),
          Vector(
            Vector("110"), Vector("111")
          )
        )
      )
    )
  }

}

This gist is the answer at http://www.zhihu.com/question/37118044/answer/70676748