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 9.2.1) (judge verdict: Accepted)

#include<bits/stdc++.h>
using namespace std;
///Welcome to Nasif's Code
#define bug printf("bug\n");
#define bug2(var) cout<<#var<<" "<<var<<endl;
#define co(q) cout<<q<<endl;
typedef long long int ll;
typedef unsigned long long int ull;
const int MOD = (int)1e9+7;
const int MAX = 1e6;
#define pi acos(-1)
#define inf 1000000000000000LL
#define FastRead    ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
int main()
{
    FastRead
    //freopen("output.txt", "w", stdout);
    string x,y,z;
    cin>>x>>y>>z;
    cout<<x[0]<<y[1]<<z[2]<<endl;

    return 0;
}