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: Wrong Answer)

#include <stdio.h>
#include <math.h>
#include <string.h>

int main(void){

	int in[2]={0};
	
	char tmp;
	int i,j;
	int count=0;
	int rev=0,num=0;
	scanf("%d %d",&in[0],&in[1]);
	//printf("%d %d\n",in[0],in[1]);
	
	for(i=in[0];i<=in[1];i++){
		
		num=i;
		rev=0;
		while(num>0){
			rev=rev*10+num%10;
			num/=10;
		}
		
		if(i==rev){
			count++;
		}
	}
	
	printf("%d",count);	
	
	return 0;
}