While working on his project, Rishi ended up with an interesting problem as follows -

There is a string $S$ which is broken down into $N$ chunks (substrings) satisfying the below constraints:

1. For each chunk except the first, starting $4$ characters will be overlapping with ending $4$ characters of atleast one chunk.
2. For each chunk except the last, ending $4$ characters will be overlapping with starting $4$ characters of atleast one chunk.

Image for the reference:

Your task is to find original message from the given chunks. If multiple solutions exists, then print all of them in lexicographical order.

Note: Number of chunks and overlaps in each test case are generated in a way that it will always pass within given time constriants.

Input Format:

First line contains an integer $N$ - the number of chunks
The next $N$ line's contain a string each - representing a chunk

Output Format:

Print all the possible unique original messages in lexicographical order

Constraints:

$1 \leq N \leq 500 \\ 4 \leq len(chunk) \leq 100 \\$