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.*;
public class GuessANumber {

	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		int n = s.nextInt();
		int min = -2000000000, max = 2000000000;
		
		HashMap<String, String> switchSign = new HashMap<String, String>();
		switchSign.put(">", "<=");
		switchSign.put("<", ">=");
		switchSign.put(">=", "<");
		switchSign.put("<=", ">");
		
		for(int i=0; i<n; i++) {
			String sign = s.next();
			int x = Integer.parseInt(s.next());
			String answer = s.next();
			
			if(answer.equals("N"))
				sign = switchSign.get(sign);
			
			if(sign.equals(">"))
				min = Math.max(min, x+1);
			else if(sign.equals("<"))
				max = Math.min(max, x-1);
			else if(sign.equals(">="))
				min = Math.max(min, x);
			else if(sign.equals("<="))
				max = Math.min(max, x);
		}
		
		if(min>max)
			System.out.println("Impossible");
		else
			System.out.println((max));
		s.close();
	}

}