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 JavaScript (node.js v5.12) (judge verdict: Wrong Answer)

// inputに入力データ全体が入る
function Main(input) {
  // 1行目がinput[0], 2行目がinput[1], …に入る
	tmp = input.split(" ");
	//文字列から10進数に変換するときはparseIntを使います
  var getResult = input => {
    var a = parseInt(input[0])
    var b = parseInt(input[1])

    var count = 0

    var check = input =>{
      var str = input.toString()
      var str1 = str.slice(Math.floor(str.length/2))
      var str2 = str.slice(0,Math.floor(str.length/2)+1).split("").reverse().join("")
      if(str1 == str2)
        return true
      else {
        return false
      }
    }

    for(var i = a;i <= b;i++){
      if(check(i))
        count++;
    }

    console.log(count)

  }


  getResult(tmp)
	//出力

}

//*この行以降は編集しないでください（標準入出力から一度に読み込み、Mainを呼び出します）
Main(require("fs").readFileSync("/dev/stdin", "utf8"));