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 Fortran (gfortran v4.8.4) (judge verdict: Runtime Error)

program ABC_072_B_OddString
   implicit none
   integer(8) i
   character(100000) s
   read(*, *) s
   do i = 2, len_trim(s)
       s(i:i)= s(2*i-1:2*i-1)
   end do
   write(*, *) trim(s)
end program ABC_072_B_OddString