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.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.*;
import java.io.BufferedReader;
import java.io.InputStreamReader;

public class CodingLegacy {

    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        Palindrome solver = new Palindrome();

        int t = 1;

        for (int i = 0; i < t; i++) {
            solver.solve(i + 1, in, out);
        }
        out.close();
    }

    static class Palindrome {
        static long mod = 1000000007;
        static long max = (long) 1e18;

        void solve(int testNumber, InputReader in, PrintWriter out) {
            int n = in.nextInt();

            int min = (int)-2e9;
            int max = (int) 2e9;

            while(n-- > 0){
                String s = in.next();
                int p = in.nextInt();
                String q = in.next();

                if((s.equals(">=") && q.equals("Y"))  || (s.equals("<") && q.equals("N"))){
                    min = Math.max(min,p);
                } else if((s.equals(">") && q.equals("Y")) || (s.equals("<=") && q.equals("N"))){
                    min = Math.max(min,p+1);
                } else if((s.equals("<=") && q.equals("Y")) || (s.equals(">") && q.equals("N"))){
                    max = Math.min(max,p);
                } else if((s.equals("<") && q.equals("Y")) || (s.equals(">=") && q.equals("N"))){
                    max = Math.min(max,p-1);
                }
            }

            if(min<=max){
                out.println(min);
            } else {
                out.println("Impossible");
            }
        }
    }
    static class InputReader {
        BufferedReader reader;
        StringTokenizer tokenizer;

        InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            tokenizer = null;
        }

        String next() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    tokenizer = new StringTokenizer(reader.readLine());
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return tokenizer.nextToken();
        }

        int nextInt(){
            return Integer.parseInt(next());
        }

        public Long nextLong(){
            return Long.parseLong(next());
        }
    }
}