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.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Locale;
import java.util.StringTokenizer;

public class Accepted {

	static StringTokenizer st;
	static BufferedReader br;
	static PrintWriter pw;

	public static void main(String[] args) throws IOException {
		Locale.setDefault(Locale.US);
		br = new BufferedReader(new InputStreamReader(System.in));
		pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter(
				System.out)));
		int n = nexInt();
		int y1 = -(int) 2e9;
		int y2 = -y1;
		for (int i = 1; i <= n; i++) {
			String s = next();
			int x = nexInt();
			String l = next();
			if (s.equals("<=")) {
				if (l.equals("Y")) {
					if (y2 > x)
						y2 = x;
				} else if (y1 < x)
					y1 = x + 1;
			}

			if (s.equals(">=")) {
				if (l.equals("Y")) {
					if (y1 < x)
						y1 = x;
				} else if (y2 > x)
					y2 = x - 1;
			}

			if (s.equals("<")) {
				if (l.equals("Y")) {
					if (y2 >= x)
						y2 = x - 1;
				} else if (y1 < x)
					y1 = x;
			}
			if (s.equals(">")) {
				if (l.equals("Y")) {
					if (y1 <= x)
						y1 = x + 1;
				} else if (y2 > x)
					y2 = x;
			}
		}
		if (y1 > y2)
			pw.print("Impossible");
		else
			pw.print(y1);
		pw.close();
	}

	private static int nexInt() throws IOException {
		return Integer.parseInt(next());
	}

	private static long nexLong() throws IOException {
		return Long.parseLong(next());
	}

	private static double nexDouble() throws IOException {
		return Double.parseDouble(next());
	}

	private static String next() throws IOException {
		while (st == null || !st.hasMoreTokens())
			st = new StringTokenizer(br.readLine());
		return st.nextToken();
	}

}