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.io.InputStream;
import java.util.Scanner;

public class CF241ADiv2 {

	String solve(int n, String[] q1, int[] q2, boolean[] q3) {
		int s = -2000000000;
		int e = 2000000000;
		for (int i = 0; i < q3.length; i++) {
			if (q1[i].equals(">")) {
				if (q3[i]) {
					int t = q2[i] + 1;
					if (s < t)
						s = t;
				} else {
					int t = q2[i];
					if (e > t)
						e = t;
				}
			} else if (q1[i].equals("<")) {
				if (q3[i]) {
					int t = q2[i] - 1;
					if (e > t)
						e = t;
				} else {
					int t = q2[i];
					if (s < t)
						s = t;
				}
			} else if (q1[i].equals(">=")) {
				if (q3[i]) {
					int t = q2[i];
					if (s < t)
						s = t;
				} else {
					int t = q2[i] - 1;
					if (e > t)
						e = t;
				}
			} else if (q1[i].equals("<=")) {
				if (q3[i]) {
					int t = q2[i];
					if (e > t)
						e = t;
				} else {
					int t = q2[i] + 1;
					if (s < t)
						s = t;
				}
			}
		}
		return (s <= e) ? "" + s : "Impossible";
	}

	String solve(InputStream in) {
		Scanner sc = new Scanner(in);
		int n = sc.nextInt();
		String[] q1 = new String[n];
		int[] q2 = new int[n];
		boolean[] q3 = new boolean[n];
		for (int i = 0; i < n; i++) {
			q1[i] = sc.next();
			q2[i] = sc.nextInt();
			q3[i] = sc.next().equals("Y");
		}
		return solve(n, q1, q2, q3);
	}

	public static void main(String[] args) {
		System.out.println(new CF241ADiv2().solve(System.in));
	}
}