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 Python (3.4.3) (judge verdict: Accepted)

s=str(input())
sx=[i for i in s]
l=len(sx)
x=[]
y=[]
for i in range(l):
    if i%2==0:
        x.append(sx[i])
    else:
        y.append(sx[1])
print("".join(x))