#Lutece1306. Key Words

Key Words

Migrated from Lutece 1306 Key Words

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Description

Given the target string TT, find all the palindromes which could have generated TT.

The generated way was:

Start with an empty string SS.

Suppose string PP is a palindrome.

Then, choose some position in the string (maybe the very beginning or the very end) and insert PP.

Try to do it again and again until you reach the target string.

For example, PP is aba, after a single step, SS becomes aba.

Now Insert PP into SS again, SS may become a aba ba.

If aababa is the target string, then aba is a possible solution.

Input

Only one line contains a nonempty target string TT (T200)(|T| \le 200), containing only a to z.

Output

Output all the possible solution in lexicographical order.

Samples

输入数据 1

aababa

输出数据 1

aba

输入数据 2

aaa

输出数据 2

a
aaa

Resources

The 14th UESTC Programming Contest Preliminary