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:
// http://codeforces.com/problemset/problem/416/A

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

public final class Guess
{
    Scanner in;
    boolean submit = true;
    
    public static void main(String args[]) throws Exception
    {
        new Guess().run();
        System.exit(0);
    }
    
    void run() throws Exception
    {
        if (!submit)
            in = new Scanner(new FileReader("testdata.txt"));
        else
            in = new Scanner(System.in);
        
        int lines = in.nextInt();
        int low = -1000000001;
        int high = 1000000001;
        
        String sign;
        int guess;
        String answer;
        
        for (int i = 0; i < lines; i++)
        {
            sign = in.next();
            guess = in.nextInt();
            answer = in.next();
            
            if (answer.equals("N"))
                sign = reverse(sign);
            
            if (sign.charAt(0) == '<' && guess <= high)
            {
                high = guess;
                if (sign.length() == 1) // strictly less than
                    high--;
            }
            else if (sign.charAt(0) == '>' && low <= guess)
            {
                low = guess;
                if (sign.length() == 1) // strictly greater than
                    low++;
            }
        }
        
        if (high < low)
            System.out.println("Impossible");
        else
            System.out.println(low);
    }
    
    String reverse(String sign)
    {
        switch (sign)
        {
            case "<":
                return ">=";
            case ">":
                return "<=";
            case "<=":
                return ">";
            case ">=":
                return "<";
            default:
                return null;
        }
    }
}