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.*;



public class Main{


    public static void main(String[] args) throws IOException{
        Reader sc = new Reader();

        int n = sc.nextInt();

        int max = 2000000000;
        int min= -2000000000;


        for(int i=0; i<n; i++){
            String[] l = sc.next().split(" ");
            if(l[0].equals(">=")){
                if(l[2].equals("Y")){
                    if(Integer.valueOf(l[1])>min){
                        min = Integer.valueOf(l[1]);

        //System.out.println(min +" "+max);
                    }
                }
                else{
                    if(Integer.valueOf(l[1])-1<max){
                        max = Integer.valueOf(l[1]) - 1;

        //System.out.println(min +" "+max);
                    }
                }

            }
            if(l[0].equals(">")){
                if(l[2].equals("Y")){
                    if(Integer.valueOf(l[1])+1>min){
                        min = Integer.valueOf(l[1])+1;

        //System.out.println(min +" "+max);
                    }
                }
                else{
                    if(Integer.valueOf(l[1])<max){
                        max = Integer.valueOf(l[1]);

        //System.out.println(min +" "+max);
                    }
                }

            }
            if(l[0].equals("<=")){
                if(l[2].equals("Y")){
                    if(Integer.valueOf(l[1])<max){
                        max = Integer.valueOf(l[1]);

        //System.out.println(min +" "+max);
                    }
                }
                else{
                    if(Integer.valueOf(l[1])+1>min){
                        min = Integer.valueOf(l[1])+1;

        //System.out.println(min +" "+max);
                    }
                }

            }
            if(l[0].equals("<")){
                if(l[2].equals("Y")){
                    if(Integer.valueOf(l[1])-1<max){
                        max = Integer.valueOf(l[1]) - 1;

        //System.out.println(min +" "+max);
                    }
                }
                else{
                    if(Integer.valueOf(l[1])>min){
                        min = Integer.valueOf(l[1]);

        //System.out.println(min +" "+max);
                    }
                }


            }
            

        }

        if(min>max){
            System.out.println("Impossible");
            return;
        }
        System.out.println(min);
        
    }
    
}


/*Reader class*/
class Reader
{
    BufferedReader br;
    StringTokenizer tk;
    Reader() throws IOException
    {
        br=new BufferedReader(new InputStreamReader(System.in));
        tk=new StringTokenizer("");
    }
    public int nextInt() throws IOException
    {
        while(!tk.hasMoreTokens())
        {
            tk=new StringTokenizer(br.readLine().replaceAll("\r",""));
        }
        return Integer.parseInt(tk.nextToken());
    }
    public Float nextFloat() throws IOException
    {
        while(!tk.hasMoreTokens())
        {
            tk=new StringTokenizer(br.readLine().replaceAll("\r",""));
        }
        return Float.parseFloat(tk.nextToken());
    }
    public String next() throws IOException
    {
        return br.readLine();
    }
}