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".

-----Input-----

The first line of the input contains a single integer n (1 ≤ n ≤ 10000) — the number of questions (and answers). Next n lines each contain one question and one answer to it. The format of each line is like that: "sign x answer", where the sign is: ">" (for the first type queries), "<" (for the second type queries), ">=" (for the third type queries), "<=" (for the fourth type queries).

All values of x are integer and meet the inequation - 10^9 ≤ x ≤ 10^9. The answer is an English letter "Y" (for "yes") or "N" (for "no").

Consequtive elements in lines are separated by a single space.

-----Output-----

Print any of such integers y, that the answers to all the queries are correct. The printed number y must meet the inequation - 2·10^9 ≤ y ≤ 2·10^9. If there are many answers, print any of them. If such value doesn't exist, print word "Impossible" (without the quotes).

-----Examples-----

Input 4

= 1 Y < 3 N <= -3 N 55 N

Output 17

Input 2

100 Y < -100 Y

Output Impossible