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 C (GCC 5.4.1) (judge verdict: Accepted)

/*
 AtCoder XXX 000
 */
 
#include <stdio.h>

int main(void){
  char a,b,c;
  char out[4];
  
  scanf("%c%c%c\n",&a,&b,&c);
  out[0]=a;
  scanf("%c%c%c\n",&a,&b,&c);
  out[1]=b;
  scanf("%c%c%c\n",&a,&b,&c);
  out[2]=c;
  
  printf("%c%c%c",out[0],out[1],out[2]);
  return 0;
}