Problem:
Score : 200 points

Problem Statement

You are given a string s consisting of lowercase English letters. Extract all the characters in the odd-indexed positions and print the string obtained by concatenating them. Here, the leftmost character is assigned the index 1.

Constraints

Each character in s is a lowercase English letter.

1≤|s|≤10^5

Input

The input is given from Standard Input in the following format:

s

Output

Print the string obtained by concatenating all the characters in the odd-numbered positions.

Sample Input 1

atcoder

Sample Output 1

acdr

Extract the first character a, the third character c, the fifth character d and the seventh character r to obtain acdr.

Sample Input 2

aaaa

Sample Output 2

aa

Sample Input 3

z

Sample Output 3

z

Sample Input 4

fukuokayamaguchi

Sample Output 4

fkoaaauh

Solution in C (GCC 5.4.1) (judge verdict: Runtime Error)

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

void Oddstring(const char *s,char *c){
        int i,j=1,len;
        len = strlen(s);
        c[0]=s[0];
        for(i=1;i<len;i++){                                                                    
                  if(i%2==0){
                        c[j++]=s[i];
                }
        }
}

int main(void)
{
        char str1[100]={0},str2[100]={0};

        scanf("%s",str1);

        Oddstring(str1,str2);
        printf("%s",str2);

        return 0;
}