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:
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
//package a;

import java.io.*;
import java.util.*;

/**
 *
 * @author Vlad
 */
public class A {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws IOException {
        InputReader in = new InputReader(System.in);
        PrintWriter out = new PrintWriter(System.out);
        
        int n = in.nextInt();
        long left = -2*1000000000;
        long right = 2*1000000000;
        
        for (int i = 0; i < n; i++) {
            
            String  stan    = in.next();
            long    nom     = in.nextLong();
            String  ans     = in.next();
            int     t       = 0;
          
            
            if (stan.charAt(0) == '>') {
                if (stan.length() == 2) t = 0; else t = 1; 
                if (ans.equals("Y")) {
                    left    = Math.max(left, nom+t) ;
                } else {
                    right   = Math.min(right, nom-(1-t) );
                }
            }
            if (stan.charAt(0) == '<') {
                if (stan.length() == 2) t = 0; else t = 1; 
                if (ans.equals("Y")) {
                    right   = Math.min(right, nom-t);
                } else {
                    left    = Math.max(left, nom-(1-t));
                }
            }
            
            //out.println(left + " " + right);
            
        }
        //out.println(left + " " + right);
        if (left > right) {
            out.println("Impossible");
        } else {
            out.println((left + right) /2);
        }
        
        out.close();
        // TODO code application logic here
    }
    
}


class InputReader {
    private final BufferedReader reader;
    private StringTokenizer tokenizer;
    
    InputReader(InputStream stream) {
        reader = new BufferedReader(new InputStreamReader(stream));
        tokenizer = new StringTokenizer("");
    }
    
    public String getLine() {
        try {
            return reader.readLine();
        } catch (IOException ex) {
            throw new RuntimeException(ex);
        }
    }
    
    public String next() throws IOException {
        while (!tokenizer.hasMoreTokens()) {
            tokenizer = new StringTokenizer(reader.readLine());
        }
        return tokenizer.nextToken();
    }
    
    public int nextInt() throws IOException {
        return Integer.parseInt(next());
    }
    
    public long nextLong() throws IOException {
        return Long.parseLong(next());
    }
    
    public double nextDouble () throws IOException {
        return Double.parseDouble(next());
    }
      
}