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Is it incompletely described? Or it is me? [problem from another OJ]
Difference between en7 and en8, changed 24 character(s)
Hello everyone!↵

Yesterday I read this problem ([](, and after that, it showed to me that there is a waste of some information that the solver needs to solve it.↵

But, surely, several unaccessible accepted submissions, made me incline to accuse my understanding.↵

So I, gratefully, hope you to help me in this problem.↵

After you read the problem statement, see this please:↵

IsAre there, in the statement, expressions that describes the **whole** way to construct the _expansion_ string from the _poly-line_ ( _initial_ ) string?↵
I saw that there is not enough 
clear explanation onfor it. So, all of the ways are considered true, but according to the examples, not all of the ways to construct the expansion string are accepted!!.↵
Thanks in advance.


  Rev. Lang. By When Δ Comment
en8 English MahmoudAlio 2018-01-01 22:59:56 24
en7 English MahmoudAlio 2018-01-01 22:57:09 86
en6 English MahmoudAlio 2017-12-31 19:07:01 5 Tiny change: 'hat there are waste of ' -> 'hat there is a waste of '
en5 English MahmoudAlio 2017-12-31 19:03:20 8 Tiny change: '\n\nSo I, thankfully, hop' -> '\n\nSo I, gratefully, hop'
en4 English MahmoudAlio 2017-12-31 17:46:15 6
en3 English MahmoudAlio 2017-12-31 17:17:19 6
en2 English MahmoudAlio 2017-12-31 17:15:23 2 Tiny change: 'veryone!\nYesterda' -> 'veryone!\n\nYesterda'
en1 English MahmoudAlio 2017-12-31 17:14:20 782 Initial revision (published)