Problem Statement

You are given a string $S$ of even length consisting of lowercase English letters. Let $|S|$ be the length of $S$, and $S_i$ be the $i$-th character of $S$.

Perform the following operation for each $i = 1, 2, \\ldots, \\frac{|S|}{2}$ in this order, and print the final $S$.

• Swap $S_{2i-1}$ and $S_{2i}$.

Constraints

• $S$ is a string of even length consisting of lowercase English letters.
• The length of $S$ is at most $100$.

Input

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

$S$

Output

Print the answer.

Sample Input 1

abcdef

Sample Output 1

badcfe

Initially, $S =$ abcdef.
Performing the operation for $i = 1$ swaps $S_1$ and $S_2$, making $S =$ bacdef.
Performing the operation for $i = 2$ swaps $S_3$ and $S_4$, making $S =$ badcef.
Performing the operation for $i = 3$ swaps $S_5$ and $S_6$, making $S =$ badcfe.
Thus, badcfe should be printed.

Sample Input 2

aaaa

Sample Output 2

aaaa

Sample Input 3

atcoderbeginnercontest

Sample Output 3

taocedbrgeniencrnoetts