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 left = -2000000000;
        int right = -left;
        int n = ni();
        for (int i = 0; i < n; i++) {
            String s = ns();
            int x = ni();
            String answer = ns();
            if (answer.equals("N")) {
                if (s.equals("<")) s = ">="; else
                    if (s.equals(">")) s = "<="; else
                        if (s.equals(">=")) s = "<"; else
                            s = ">";
            }
            if (s.equals(">")) {
                left = Math.max(left, x + 1);
            } else if (s.equals("<")) {
                right = Math.min(right, x - 1);
            } else if (s.equals(">=")) {
                left = Math.max(left, x);
            } else {
                right = Math.min(right, x);
            }
        }
        if (left > right) out.println("Impossible");
        else out.println(left);
	}
	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());
	}
}