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.HashMap;
import java.util.Scanner;


public class A {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int INF = 2000000000;
		int N = sc.nextInt();
		int L = -INF;
		int R = INF;
		
		HashMap<String, String> rev = new HashMap<String, String>();
		rev.put("<", ">=");
		rev.put("<=", ">");
		rev.put(">", "<=");
		rev.put(">=", "<");
		
		for(int i = 0; i < N; i++) {
			String sig = sc.next();
			int x = sc.nextInt();
			boolean yes = sc.next().charAt(0) == 'Y';
			if(yes == false) {
				sig = rev.get(sig);
			}
			if(sig.equals("<")) {
				R = Math.min(R, x-1);
			} else if(sig.equals("<=")) {
				R = Math.min(R, x);
			} else if(sig.equals(">")) {
				L = Math.max(L, x+1);
			} else if(sig.equals(">=")) {
				L = Math.max(L, x);
			}
		}
		
		if(L <= R) {
			System.out.println(L);
		} else {
			System.out.println("Impossible");
		}
	}
}