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 Main {
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		int n = Integer.parseInt(sc.nextLine());
		int a[] = new int[4];
		a[0] = -2*1000000000;
		a[1] = -2*1000000000;
		a[2] = 2*1000000000;
		a[3] = 2*1000000000;
		int y = -2*1000000000;
		for(int i =0; i<n;i++){
			String line = sc.nextLine();
			//System.out.println(line);
			String temp[] = line.split(" ");
			//System.out.println(temp.length);
			if(temp[0].equals(">=")){
				if(temp[2].equals("Y")){
					a[0]=Math.max(a[0],Integer.parseInt(temp[1]));
				}
				else{
					a[2]=Math.min(a[2],Integer.parseInt(temp[1]));
				}
			}
			else if(temp[0].equals(">")){
				if(temp[2].equals("Y")){
					a[1]=Math.max(a[1],Integer.parseInt(temp[1]));
				}
				else{
					a[3]=Math.min(a[3],Integer.parseInt(temp[1]));
				}
				
			}
			else if(temp[0].equals("<")){
				if(temp[2].equals("Y")){
					a[2]=Math.min(a[2],Integer.parseInt(temp[1]));
				}
				else{
					a[0]=Math.max(a[0],Integer.parseInt(temp[1]));
				}
				
			}
			else{
				if(temp[2].equals("Y")){
					a[3]=Math.min(a[3],Integer.parseInt(temp[1]));
				}
				else{
					a[1]=Math.max(a[1],Integer.parseInt(temp[1]));
				}
			}
		}
		boolean possible = true;
		if(a[0]>a[1]){
			y = a[0];
		}
		else y = a[1]+1;
		if(y<a[2]){
			if(y>a[3]){
				possible = false;
			}
		}
		else{
			possible = false;
		}
		if(possible){System.out.println(y);}
		else {
			System.out.println("Impossible");
		}
	}

}