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.*;
import java.io.*;
import java.math.*;
import java.awt.*;
public class Guess
{
    static final int INF = Integer.MAX_VALUE;
    static final int NINF = Integer.MIN_VALUE;
   
    public static void main(String[]args)throws IOException
    {
        Input in = new Input();
        int m = in.nextInt();
        int low = -2*1000000000;
        int high = 2*1000000000;
        for(int i = 0; i < m; i++)
        {
            String s = in.next();
            int n = in.nextInt();
            String ans = in.next();
            if(s.equals("<"))
            {
                if(ans.equals("Y"))
                    high = Math.min(high, n-1);
                else
                    low = Math.max(low, n);
            }else if(s.equals("<="))
            {
                if(ans.equals("Y"))
                    high = Math.min(high, n);
                else
                    low = Math.max(low, n+1);
            }else if(s.equals(">"))
            {
                if(ans.equals("Y"))
                    low = Math.max(low, n+1);
                else
                    high = Math.min(high, n);
            }else if(ans.equals("Y"))
                low = Math.max(n, low);
            else
                high = Math.min(high, n-1);

            if(high < low)
            {
                System.out.println("Impossible");
                return;
            }
            //System.out.println(low+" "+high);
        }
        System.out.println(low);
    }

    public static void exit()
    {
        System.exit(0);
    }
}

class Input
{
    BufferedReader br;
    StringTokenizer st;

    public Input()
    {
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    public String nextLine()throws IOException
    {
       return br.readLine();
    }

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

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

    public float nextFloat()throws IOException
    {
        return Float.parseFloat(next());
    }

    public double nextDouble()throws IOException
    {
        return Double.parseDouble(next());
    }

    public String next()throws IOException
    {
        if(st == null || !st.hasMoreTokens())
          st = new StringTokenizer(br.readLine());
        return st.nextToken();
    }
}