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 GuessAnumber {
	static Long upperBoundry = 1998638045L;
							   
	static Long lowerBoundry = 1998638045L*-1L;
							
	public static void main(String[] args) {
		Scanner s = new Scanner(System.in);
		int n = s.nextInt();
//		Stack<String[]> stack = new Stack<>();
		String []str = new String[3];
		while(n-- >0) {
			str[0] = s.next(); 
			str[1] = s.next(); 
			str[2] = s.next();
//			stack.push(str);
			updateBoundries(str);
		}
		
		 if(lowerBoundry > upperBoundry) {
			System.out.println("Impossible");
		} else {
			System.out.println(lowerBoundry);
		}
	}
	
	public static void updateBoundries(String[] str) {
		Long number = Long.parseLong(str[1]);
		if(str[0].startsWith("<")) {
			if(str[2].equals("Y") && upperBoundry >= number) {
				if(str[0].contains("="))
					upperBoundry = number;
				else
					upperBoundry = number-1;
			} else if(str[2].equals("N") && lowerBoundry <= number){							
				if(str[0].contains("="))
					lowerBoundry=number+1;
				else
					lowerBoundry = number;
			}
		} else {
			if(str[2].equals("Y") && lowerBoundry <= number) {

				if(str[0].contains("="))
					lowerBoundry = number;
				else
					lowerBoundry = number+1;
			} else if(str[2].equals("N") && upperBoundry >= number) {
				if(str[0].contains("="))
					upperBoundry=number-1;
				else
					upperBoundry = number;
							
			}
		}
		
	
	}
}