Problem:
Score : 300 points

Problem Statement

You are given an integer sequence of length n, a_1, ..., a_n.
Let us consider performing the following n operations on an empty sequence b.

The i-th operation is as follows:

Append a_i to the end of b.

Reverse the order of the elements in b.

Find the sequence b obtained after these n operations.

Constraints

1 \leq n \leq 2\times 10^5

0 \leq a_i \leq 10^9

n and a_i are integers.

Input

Input is given from Standard Input in the following format:

n
a_1 a_2 ... a_n

Output

Print n integers in a line with spaces in between.
The i-th integer should be b_i.

Sample Input 1

4
1 2 3 4

Sample Output 1

4 2 1 3

After step 1 of the first operation, b becomes: 1.

After step 2 of the first operation, b becomes: 1.

After step 1 of the second operation, b becomes: 1, 2.

After step 2 of the second operation, b becomes: 2, 1.

After step 1 of the third operation, b becomes: 2, 1, 3.

After step 2 of the third operation, b becomes: 3, 1, 2.

After step 1 of the fourth operation, b becomes: 3, 1, 2, 4.

After step 2 of the fourth operation, b becomes: 4, 2, 1, 3.

Thus, the answer is 4 2 1 3.

Sample Input 2

3
1 2 3

Sample Output 2

3 1 2

As shown above in Sample Output 1, b becomes 3, 1, 2 after step 2 of the third operation. Thus, the answer is 3 1 2.

Sample Input 3

1
1000000000

Sample Output 3

1000000000

Sample Input 4

6
0 6 7 6 7 0

Sample Output 4

0 6 6 0 7 7

Solution in Scala (2.11.7) (judge verdict: Accepted)

import scala.io.StdIn
import scala.collection.mutable.ListBuffer
import scala.annotation.tailrec

object Main extends App {
  val out = new java.io.PrintWriter(System.out)
  val n = StdIn.readInt
  val a = StdIn.readLine.split(" ").map(_.toInt)

  @tailrec
  def rec(b:ListBuffer[Int], cnt:Int, num:Iterator[Int]):Unit = {
      if(num.hasNext) {
        if((cnt&1) == 0) rec(b += num.next, cnt+1, num)
        else rec(num.next +=: b, cnt+1, num)
      } else return
  }

  val b = ListBuffer.empty[Int]
  val ite = a.iterator

  if((n&1) == 0) rec(b, 0, ite)
  else rec(b, 1, ite)

  out.println(b.mkString(" "))
  out.flush
}