Short Long Short String

Background

Congcong is learning how to manipulate strings and wants to try a special concatenation method.

Problem Description

Given two strings, $a$ and $b$, return a string of the form short+long+short, with the shorter string on the outside and the longer string on the inside. The strings will not be the same length, but they may be empty (length $0$).

Input Format

Input is given from standard input in the following format.

Two strings $a$ and $b$, separated by a space.

Output Format

Output is printed to standard output in the following format.

The concatenated string.

Sample

Hello hi

hiHellohi

hi Hello

hiHellohi

aaa b

baaab

Sample Explanation

For Sample 1, string "Hello" has length $5$, and string "hi" has length $2$. The shorter string is "hi\