There is a genre of fiction called choose your own
adventure books.
These books allow the reader to make choices for
the characters which altersthe outcome of the story.

For example, after reading the first page of a book, the reader may
be asked a choice, such as “Do you pick up the rock?” If the reader
answers “yes”, they are directed to continue reading on page 47, and if
they choose “no”, they are directed to continue reading on page 18. On
each of those pages, they have further choices, and so on, throughout
the book. Some pages do not have any choices, and thus these are the
“ending” pages of that version of the story. There may be many such
ending pages in the book, some of which are good (e.g., the hero finds
treasure) and others which are not (e.g., the hero finds a leftover
sandwich from 2001).

You are the editor of one of these books, and you must examine two
features of the choose your own adventure book:

• ensure that every page can be reached – otherwise, there is no
  reason to pay to print a page which no one can ever read;

• find the shortest path, so that readers will know what the
  shortest amount of time they need to finish one version of the
  story.

Given a description of the book, examine these two features.

\((1 \leq N \leq 10000)\)
\((1 \leq i \leq N; 0 \leq M_i \leq N)\)
\(N \leq 100\)
\(M_i \leq 10\)
\(1 \le i \le N\)
\(N \leq 1000\)
\(M_i \le 25\)

The first line of input contains \(N\)
\((1 \leq N \leq 10000)\), the number
of pages in the book. Each of the next \(N\) lines contain an integer \(M_i\) \((1 \leq i \leq N; 0 \leq M_i \leq N)\), which is the number of different
options from page \(i\), followed by
\(M_i\) space-separated integers in the
range from \(1\) to \(N\), corresponding to each of the pages to
go to next from page \(i\). It will
also be the case \(M_1 + M_2 + \cdots + M_N\) is at most 10000.

If \(M_i = 0\), then page \(i\) is an ending page (i.e., there are no
choices from that page). There will be at least one ending page in the
book.

Note that you always begin the book on page 1.

For 4 of the available 15 marks, \(N \leq 100\), \(M_i \leq 10\) for \(1 \le i \le N\).

For an additional 3 of the available 15 marks, the book is guaranteed
to have no cycles.

For an additional 4 of the available 15 marks, \(N \leq 1000\), \(M_i \le 25\) for \(1 \le i \le N\).

The output will be two lines. The first line will contain
Y if all pages are reachable, and
N otherwise. The last line will contain a
non-negative integer \(K\), which is
the shortest path a reader can take while reading this book. There will
always be a finite shortest path.

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출처 CCC 2018 Junior