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.ArrayList;
import java.util.Random;
import java.util.Scanner;


public class A_Guess_a_number {
    public static void main(String[] args) {
        
        
            calc();
        }
    
    public static void calc(){
        int b = pow(-10,9) ;
        int e =pow(10, 9) ;
        ArrayList<String> q = new ArrayList<>();
        ArrayList<Integer> n = new ArrayList<>();
        ArrayList<String> ans = new ArrayList<>();
        
        
        
        Scanner scan  = new Scanner(System.in);
        String l = scan.nextLine();
        for (int i = 0; i < Integer.parseInt(l); i++) {
            String m = scan.nextLine();
            String[] p = m.split(" ");
//          System.out.println(p[0]);
            q.add(p[0]);
            n.add(Integer.parseInt(p[1]));
            ans.add(p[2]);
            
        }
        
    
        for (int i = 0; i < q.size(); i++) {
            if(q.get(i).equals(">=")){
                if(ans.get(i).equals("Y")){
                    if(n.get(i)>=b)
                        b = n.get(i);
                }
                else
                    if(n.get(i) <= e)
                        e = n.get(i)-1 ;
            }
            
            else if(q.get(i).equals(">") ){
                if(ans.get(i).equals("Y")){
                    if(n.get(i)>=b)
                        b = n.get(i)+1;
                }
                else
                    if(n.get(i) <= e)
                        e = n.get(i) ;
            }
            else if(q.get(i).equals("<")){
                if(ans.get(i).equals("Y")){
                        if(n.get(i)<= e)
                            e = n.get(i)-1 ;
//                      System.out.println("AS");
                }
                else
                    if(n.get(i) >= b)
                        b = n.get(i);
            }
            else if(q.get(i).equals("<=")){
                if(ans.get(i).equals("Y")){
                    if(n.get(i)<= e)
                        e = n.get(i) ;
                }
                else
                    if(n.get(i) >= b)
                        b = n.get(i)+1;
            }
//          System.out.println(b+" "+e);
        }
        
        if(Math.abs(b) == pow(10,9) || Math.abs(e) == pow(10,9)){
//          System.out.println(n.get(0));
            if(Math.abs(b) == pow(10,9)) System.out.println(e);
            else System.out.println(b);
        }
        else
            if(b>e )
                System.out.println("Impossible");
            else
                if(b != e) System.out.println(b+1);
                else System.out.println(b);
        
        
        
        
    }   
    
    public static int pow(int b , int exp){
        if(exp == 0) return 1 ;
         int res = pow(b , exp/2);
         res *= res ;
         if(exp %2 == 1){
             res*=b;
         }
         return res;
    }
}