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.Scanner;

public class Guess_a_number {
    public static void main(String args[]){
            Scanner in = new Scanner(System.in);            
            int n = in.nextInt();
            String s[] = new String[n];
            int x[] = new int[n];
            char ans[] = new char[n];
            for(int i=0; i < n; i++){
                s[i] = in.next();
                x[i] = in.nextInt();
                ans[i] = in.next().charAt(0);
            }
            long marz_l = -2000000000 , marz_r = 2000000000 ;
            for(int i=0; i < n ; i++){
                if(s[i].equals("<")){
                    if(ans[i]=='Y'){
                        if(x[i]-1<marz_r)
                            marz_r = x[i]-1;
                    }
                    else{
                        if(x[i]>marz_l)
                            marz_l = x[i];
                    }
                }else if(s[i].equals(">")){
                    if(ans[i]=='Y'){
                        if(x[i]+1>marz_l)
                            marz_l = x[i]+1;
                    }else{
                        if(x[i]<marz_r)
                            marz_r = x[i];
                    }
                }else if(s[i].equals(">=")){
                    if(ans[i]=='Y'){
                        if(x[i]-1>marz_l)
                            marz_l = x[i];
                    }else{
                        if(x[i]-1<marz_r)
                            marz_r = x[i]-1;
                    }
                }else if(s[i].equals("<=")){
                    if(ans[i]=='Y'){
                        if(x[i]<marz_r)
                            marz_r = x[i];
                    }else{
                        if(x[i]+1>marz_l)
                            marz_l = x[i]+1;
                    }
                }
            }
            if(marz_r>marz_l){
                System.out.println(marz_l+1);
            }else if(marz_r==marz_l)
                System.out.println(marz_l);
            else
                System.out.println("Impossible");
            
    }
}