Problem:
Score : 100 points

Problem Statement

We have a 3×3 square grid, where each square contains a lowercase English letters.
The letter in the square at the i-th row from the top and j-th column from the left is c_{ij}.

Print the string of length 3 that can be obtained by concatenating the letters in the squares on the diagonal connecting the top-left and bottom-right corner of the grid, from the top-left to bottom-right.

Constraints

Input consists of lowercase English letters.

Input

Input is given from Standard Input in the following format:

c_{11}c_{12}c_{13}
c_{21}c_{22}c_{23}
c_{31}c_{32}c_{33}

Output

Print the string of length 3 that can be obtained by concatenating the letters on the diagonal connecting the top-left and bottom-right corner of the grid, from the top-left to bottom-right.

Sample Input 1

ant
obe
rec

Sample Output 1

abc

The letters in the squares on the diagonal connecting the top-left and bottom-right corner of the grid are a, b and c from top-right to bottom-left. Concatenate these letters and print abc.

Sample Input 2

edu
cat
ion

Sample Output 2

ean

Solution in Scala (2.11.7) (judge verdict: Runtime Error)

object Main extends App {

  val In = io.StdIn.readLine()
  val A = In.split(" ")

  val max:Int = A.max.toInt
  val min:Int = A.min.toInt

  //var arr = Array.ofDim[Int](A(0).toInt, A(1).toInt)

  var N = 0

  if (min == 1) {
    if (max == 1) {
      N = 1
    }else {
        N = max - 2
    }
  }

  if (min == 2) {
    N = 0
  }

  if (min >= 3){
    N = (A(0).toInt - 2) * (A(1).toInt - 2)
  }

  print(N)

}