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.*;
import java.util.*;

public class Main {
    static class Reader {
        private BufferedReader br;
        private StringTokenizer token;
        protected Reader(InputStream obj) {
            br = new BufferedReader(new InputStreamReader(obj));
            token = null;
        }
        protected String next() {
            while (token == null || !token.hasMoreElements()) {
                try {
                    token = new StringTokenizer(br.readLine());
                } catch (IOException e) {e.printStackTrace();}
            } return token.nextToken();
        }
        protected int nextInt() {return Integer.parseInt(next());}
        protected long nextLong() {return Long.parseLong(next());}
        protected double nextDouble() {return Double.parseDouble(next());}
    }

    public static void main(String[] args) throws IOException {
        Reader in = new Reader(System.in);
        PrintWriter out = new PrintWriter(System.out);
        int n = in.nextInt(), l = -2_000_000_000, r = 2_000_000_000;
        boolean sol = false;
        while (n-->0) {
            String rel = in.next(); int x = in.nextInt(); char ans = in.next().charAt(0);
            if (rel.equals(">")) {
                if (ans == 'Y') l = Math.max(x+1, l);
                else r = Math.min(x, r);
            } else if (rel.equals("<")) {
                if (ans == 'Y') r = Math.min(x-1, r);
                else l = Math.max(x, l);
            } else if (rel.equals(">=")) {
                if (ans == 'Y') l = Math.max(x, l);
                else r = Math.min(x-1, r);
            } else { // "<="
                if (ans == 'Y') r = Math.min(x, r);
                else l = Math.max(x+1, l);
            }
            if (l>r) {
                sol = true;
                break;
            }
        }
        if (l>r || sol) out.println("Impossible");
        else out.println(l);

        out.close();
    }
}