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.*;
public class gn241
{
	public static void main(String ar[])
	{
		Scanner obj=new Scanner(System.in);
		int n=obj.nextInt();
		
		int ans=2000000000;
		int ans1=-2000000000;
		for(int i=1;i<=n;i++)
		{
			String ch=obj.next();
		int num=obj.nextInt();
		String r=obj.next();
		String ch1="";
			if(r.equals("N"))
			{
				if(ch.equals("<")){
				ch1= ">=";ans1=Math.max(ans1, num);}
				if(ch.equals(">")){
				ch1= "<=";ans=Math.min(ans, num);}
				if(ch.equals("<=")){
				ch1= ">";ans1=Math.max(ans1, num+1);}
				if(ch.equals(">=")){
				ch1="<";ans=Math.min(ans, num-1);}
				//System.out.println(ch1);
			}
			else{
		if (ch.equals( ">=")) ans1=Math.max(ans1, num);
		else if (ch.equals(">")) ans1=Math.max(ans1, num+1);
		else if (ch.equals( "<="))ans=Math.min(ans, num);
		else ans=Math.min(ans, num-1);
	}}
	if (ans1 <= ans) 
	System.out.println(ans);
	else System.out.println("Impossible");
	}
}