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 Main {

	public static String turn(String sign, String ok) {
		if ("Y".equals(ok)) {
			return sign;
		}
		else {
			if (">".equals(sign)) {
				return "<=";
			}
			else if (">=".equals(sign)) {
				return "<";
			}
			else if ("<".equals(sign)) {
				return ">=";
			}
			else {
				return ">";
			}
		}
	}

	public static void main(String[] agrs) {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		int mi = -2000000000;
		int ma = -mi;
		for (int ca = 1; ca <= n; ca ++) {
			String sign = in.next();
			int num = in.nextInt();
			String ok = in.next();
			sign = turn(sign, ok);
			if (">".equals(sign)) {
				mi = Math.max(mi, num + 1);
			}
			else if (">=".equals(sign)) {
				mi = Math.max(mi, num);
			}
			else if ("<".equals(sign)) {
				ma = Math.min(ma, num - 1);
			}
			else if ("<=".equals(sign)) {
				ma = Math.min(ma, num);
			}
		}
		if (ma < mi) {
			System.out.println("Impossible");
		}
		else {
			System.out.println(ma);
		}
	}
}