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.*;
public class Guess_a_number
{
    public static void main(String[] args)
    {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        sc.nextLine();
        int min = -2000000000;
        int max = 2000000000;
        for(int i = 0; i < n; i++)
        {
            String s = sc.nextLine();
            char c = s.charAt(s.length() - 1);
            if(c == 'Y')
            {
                int start = s.indexOf(" ");
                int end = s.indexOf(" ", start + 1);
                int n1 = Integer.valueOf(s.substring(start + 1, end));
                String s1 = s.substring(0, start);
                if(s1.equals("<"))
                {
                    max = Math.min(max, n1 - 1);
                }
                else if(s1.equals("<="))
                {
                    max = Math.min(max, n1);
                }
                else if(s1.equals(">"))
                {
                    min = Math.max(min, n1 + 1);
                }
                else if(s1.equals(">="))
                {
                    min = Math.max(min, n1);
                }
            }
            else
            {
                int start = s.indexOf(" ");
                int end = s.indexOf(" ", start + 1);
                int n1 = Integer.valueOf(s.substring(start + 1, end));
                String s1 = s.substring(0, start);
                if(s1.equals("<"))
                {
                    min = Math.max(min, n1);
                }
                else if(s1.equals("<="))
                {
                    min = Math.max(min, n1 + 1);
                }
                else if(s1.equals(">"))
                {
                    max = Math.min(max, n1);
                }
                else if(s1.equals(">="))
                {
                    max = Math.min(max, n1 - 1);
                }
            }
        }
        if(min > max)
        {
            System.out.println("Impossible");
        }
        else if(min == max)
        {
            System.out.println(min);
        }
        else
        {
            System.out.println(min + 1);
        }
        sc.close();
    }
}