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: Accepted)

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#define STR_LEN 100000
void fun(char *,char *);
void fun(char *str1,char *str2)
{
    int i,j=0;
    for(i=0;str1[i]!='\0';i=i+2)
    {
        str2[j++]=str1[i];
    }
    str2[j]='\0';
}
int main()
{
    char s1[STR_LEN+1]={0};
    char s2[STR_LEN+1]={0};
    scanf("%s",s1);
    fun(s1,s2);
    printf("%s\n",s2);
    return 0;
}