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The participants of the first congress of Paranoiac Informatics Society took their places at a rectangular table. All sat at the same side. One of them pose the following question: "What is the number of ways we can shake our hands without leaving our places? Each time every participant can shake hand of one person and this person must be his/her neighbour."
Since the congress participants are theoreticians, they asked you to write a program, which computes this number of ways. The participants hate big numbers, so they need only the last digit of the result.
Write a program which:
The first and only line of the standard input contains one integer ().
The first and only line of the standard output should contain one digit, i.e. the last digit of the number of ways the participants can shake hands.
For the input data:
the correct result is:
All correct ways to shake participants' hands for .
Task author: Jakub Radoszewski.