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.*;
import java.io.*;
import java.math.*;
import java.lang.*;
import java.util.stream.*;

/**
 * @author Pradyumn
 */

public class Main implements Runnable{

	public static void main(String[] args) {
		new Thread(null, new Main(), ":)", 1L << 26).start();
	}
	@SuppressWarnings("Unchecked")
	public void solve() throws IOException {
		int l = -2000000000;
		int r = -l;
		int n = ni();
		for(int i = 0;i < n; ++i) {
			String s = ns();
			int num = ni();
			String v = ns();
			if(v.equals("N")) {
				if(s.equals(">"))
					s = "<=";
				else if(s.equals("<"))
					s = ">=";
				else if(s.equals(">="))
					s = "<";
				else if(s.equals("<="))
					s = ">";
			}
			if(s.equals(">")) {
				l = Math.max(l, num + 1);
			} else if(s.equals("<")) {
				r = Math.min(r, num - 1);
			} else if(s.equals("<=")) {
				r = Math.min(r, num);
			} else {
				l = Math.max(l, num);
			}
		}
		out.println(l > r ? "Impossible" : l);  
	}
	BufferedReader br;
	StringTokenizer st;
	PrintWriter out;
	public void run() {
		try {
			br = new BufferedReader(new InputStreamReader(System.in),32768);
			st = null;
			out = new PrintWriter(System.out);
			solve();
			br.close();
			out.close();
		} catch(IOException e) {
			e.printStackTrace();
			System.exit(1);
		}
	}
	public char[] ns(int n) throws IOException {
		return ns().toCharArray();
	}
	public String ns() throws IOException {
		while (st == null || !st.hasMoreTokens()) {
			st = new StringTokenizer(br.readLine());
		}
		return st.nextToken();
	}
	public String nextLine() throws IOException {
		return br.readLine();
	}
	public int ni() throws IOException {
		return Integer.parseInt(ns());
	}

	public int[] na(int n) throws IOException {
		int[] a = new int[n];
		for(int i = 0;i < n; ++i) a[i] = ni();
		return a;
	}

	public long nl() throws IOException {
		return Long.parseLong(ns());
	}

	public long[] nal(int n) throws IOException {
		long[] a = new long[n];
		for(int i = 0;i < n; ++i) a[i] = nl();
		return a;
	}

	public double nd() throws IOException {
		return Double.parseDouble(ns());
	}
}