Problem: 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  - 109 ≤ x ≤ 109. 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  - 2·109 ≤ y ≤ 2·109. If there are many answers, print any of them. If such value doesn't exist, print word "Impossible" (without the quotes).

Examples

Input

4
&gt;= 1 Y
&lt; 3 N
&lt;= -3 N
&gt; 55 N


Output

17


Input

2
&gt; 100 Y
&lt; -100 Y


Output

Impossible

Solution (in JAVA):

Solution:
import java.util.Scanner;

public class A {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int left = -2*1000000000;
		int right = 2*1000000000;
	 	for (int i = 0; i < n; i++) {
			String op = sc.next();
			int data = sc.nextInt();
			String flag = sc.next();
			if (flag.equals("Y")) {
				if (op.equals(">"))
					left = Math.max(data + 1, left);
				if (op.equals("<"))
					right = Math.min(right, data - 1);
				if (op.equals(">="))
					left = Math.max(left, data);
				if (op.equals("<="))
					right = Math.min(right, data);
			} else {
				// > 5 N  x<=5
				if (op.equals(">"))
					right = Math.min(data, right);
				// < 5 N  x>=5
				if (op.equals("<"))
					left = Math.max(left, data);
				// >= 5 N  x<5
				if (op.equals(">="))
					right = Math.min(right, data-1);
				// <= 5 N  x>5
				if (op.equals("<="))
					left = Math.max(left, data+1);

			}

		}
		if (left > right) {
			System.out.println("Impossible");
			return;
		}
		System.out.println(left);
	}
}