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.*;
import java.util.*;
public class Main
{
	public static void main(String[] args) throws Exception
	{
	    BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
	    int n=Integer.parseInt(br.readLine());
	    int min=-1999999999,max=2147483647;
	    
	    for(int i=0;i<n;i++)
	    {
	        String s=br.readLine();
	        String str[]=s.split(" ");
	        if(str[2].equals("Y"))
	        {
	            if(str[0].equals(">=")&&min<Integer.parseInt(str[1]))
	            min=Integer.parseInt(str[1]);
	            if(str[0].equals("<=")&&max>Integer.parseInt(str[1]))
	            max=Integer.parseInt(str[1]);
	            if(str[0].equals(">")&&min<=Integer.parseInt(str[1]))
	            min=Integer.parseInt(str[1])+1;
	            if(str[0].equals("<")&&max>=Integer.parseInt(str[1]))
	            max=Integer.parseInt(str[1])-1;
	        }
	        else if(str[2].equals("N"))
	        {
	            if(str[0].equals(">=")&&max>=Integer.parseInt(str[1]))
	            max=Integer.parseInt(str[1])-1;
	            if(str[0].equals("<=")&&min<=Integer.parseInt(str[1]))
	            min=Integer.parseInt(str[1])+1;
	            if(str[0].equals(">")&&max>Integer.parseInt(str[1]))
	            max=Integer.parseInt(str[1]);
	            if(str[0].equals("<")&&min<Integer.parseInt(str[1]))
	            min=Integer.parseInt(str[1]);
	        }
	        
	    }
	    if(min<=max)
	    System.out.println(min);
	    else
	    System.out.println("Impossible");
	}
}