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 round416problema {
	static Scanner in = new Scanner(System.in);

	public static void main(String[] args) {
		
	int n=in.nextInt();
	int a=2000000000;
	int b=-2000000000;
	
	for(int i=0;i<n;i++){
		String s=in.next();
		int t=in.nextInt();
		String s1=in.next();
		
		if(s.contains(">=")){
			if(s1.contains("N")){
				if(a>t-1)
				a=t-1;
			}
			else{
				if(b<t)
				b=t;
			}
		}
		
		else if(s.contains("<=")){

			if(s1.contains("N")){
				if(b<t+1)
				b=t+1;
			}
			else{
				if(a>t)
				a=t;
			}
		}
		else if(s.contains("<")){
			
			if(s1.contains("N")){
				if(b<t)
				b=t;
			}
			else{
				if(a>t-1)
				a=t-1;
			}
		}
		
		else{

			
			if(s1.contains("N")){
				if(a>t)
				a=t;
			}
			else{
				if(b<t+1)
				b=t+1;
			}
		
		}
	}
	
	if(a<b){
		System.out.println("Impossible");
		return;
	}
	System.out.println(b);
	
	}
}