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 Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.io.*;
import java.util.*;
public class Main {
  public static void main(String[] args) throws Exception {
    String line = null;
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    line = br.readLine();
    char[] charArray = line.toCharArray();
    StringBuilder sb = new StringBuilder("");
    for (int i = 0; i < charArray.length; i ++) {
      //System.out.println(charArray[i]);
      if ((i + 1)%2 != 0) {
        sb.append(charArray[i]);
      }
    }
    System.out.println(sb.toString());
  }
}