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A. Guess a number!(cf)

A TV show called "Guess a number!" is gathering popularity. The whole Berland, the old and the young, are watching the show.

The rules are simple. The host thinks of an integer y and the participants guess it by asking questions to the host. There are four types of acceptable questions:

  • Is it true that y
     is strictly larger than number x?
  • Is it true that y is strictly smaller than number x?
  • Is it true that y is larger than or equal to number x?
  • Is it true that y is smaller than or equal to number x?

On each question the host answers truthfully, "yes" or "no".

Given the sequence of questions and answers, find any integer value of y

 that meets the criteria of all answers. If there isn't such value, print "Impossible".