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 GuessANumber {
	private static int y;
	
	private static int min = - 2000000000;
	private static int max = 2000000000;
	
	private static String yes = "Y";
	private static String no = "N";
	
	public static void main(String [] args) {
		Scanner sc = new Scanner(System.in);
		y = Integer.valueOf(sc.nextLine());
		String [] choice = new String [y];
		for (int i = 0; i < y; i++) {
			choice[i] = new String(sc.nextLine());
		}
		
		for (int i = 0; i < choice.length; i++) {
			String [] split = choice[i].split(" ");
			if (split[2].equals(no))
				split[0] = reverse(split[0]);
			
			if (split[0].equals("<")) {
				if (max > Integer.valueOf(split[1]) -1)
					max = Integer.valueOf(split[1]) - 1;
			} else if (split[0].equals("<=")) {
				if (max > Integer.valueOf(split[1]))
					max = Integer.valueOf(split[1]);
			} else if (split[0].equals(">")) {
				if (min < Integer.valueOf(split[1]) + 1)
					min = Integer.valueOf(split[1]) + 1;
			} else if (split[0].equals(">=")) {
				if (min < Integer.valueOf(split[1]))
					min = Integer.valueOf(split[1]);
			}
		}
		if (min > max) {
			System.out.println("Impossible");
		} else {
			System.out.println(min);
		}
	}

	private static String reverse(String str) {
		 if(str.equals("<"))
			 return ">=";
		 if(str.equals("<="))
			 return ">";
		 if(str.equals(">"))
			 return "<=";
		 if(str.equals(">="))
			 return "<";
		return str;
	}
}