#codefestival2015qualBa. [codefestival_2015_qualB_a]Double String
[codefestival_2015_qualB_a]Double String
Problem Statement
It is 10/25/2015
today.
This date has an interesting property as a string: all letters contained in this string (1
, 0
, 2
, 5
, /
) appear exactly twice in this string.
We will call such a string double: a string is double if and only if any letter that appears at least once in appears exactly twice in .
You are given a string consisting of lowercase alphabets. Construct and print a double string that contains all letters in .
Your output may contain letters that are not in , but may not contain letters other than lowercase alphabets.
Input
Input is given from Standard Input in the following format:
- The first line contains a string .
- consists of lowercase alphabets.
- No letter appears more than once in .
Output
Print a double string consisting of lowercase alphabets that contains all letters in . When there are multiple solutions, any of them will be accepted. Print a newline at the end of output.
Sample Input 1
on
Sample Output 1
noon
These solutions will also be accepted: onno
, onon
, oonn
and lemonmelon
.
Sample Input 2
meat
Sample Output 2
teammate