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.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;


public class Main
{
    static BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    static PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out));
    static StringTokenizer datos = new StringTokenizer("");
    
    public static void main(String[] args)throws IOException
    {
        int q = nextInt();
        int l = -2000000000;
        int r = 2000000000;
        while(q-->0){
            String eq = next();
            int v = nextInt();
            char ans = next().charAt(0);
            if(eq.equals(">=")){
                if(ans=='Y'){
                    l = Math.max(l, v);
                }else{
                    r = Math.min(r, v - 1);
                }
            }else if(eq.equals(">")){
                if(ans=='Y'){
                    l = Math.max(l, v + 1);
                }else{
                    r = Math.min(r, v);
                }
            }else if(eq.equals("<")){
                if(ans=='Y'){
                    r = Math.min(r, v - 1);
                }else{
                    l = Math.max(l, v);
                }
            }else{
                if(ans=='Y'){
                    r = Math.min(r, v);
                }else{
                    l = Math.max(l, v + 1);
                }
            }
            if(l>r){
                System.out.println("Impossible");
                return;
            }
        }
        out.println(l);
        out.flush();
    }
    
    public static String next() throws IOException
    {
        while(!datos.hasMoreTokens()){
            String s = in.readLine();
            if(s==null) return null;
            datos = new StringTokenizer(s);
        }
        return datos.nextToken();
    }
    
    public static int nextInt() throws IOException
    {
        return Integer.parseInt(next());
    }
}