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.io.*;
import java.util.*;

public class cf416a {
	public static void main(String[] args) throws Exception {
		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(in.readLine().trim());
		int l = Integer.MIN_VALUE;
		int r = Integer.MAX_VALUE;

		for(int m = 0; m < n && l <= r; m++) {
			String[] s = in.readLine().split("\\s+");
			int val = Integer.parseInt(s[1]);
			if(s[0].equals(">")) {
				if(s[2].equals("Y")) {
					if(l <= val) l = val+1;
				}
				else if(r > val) r = val;
			}
			else if(s[0].equals(">=")) {
				if(s[2].equals("Y")) {
					if(l < val) l = val;
				}
				else if(r >= val) r = val-1;
			}
			else if(s[0].equals("<")) {
				if(s[2].equals("Y")) {
				       if(r >= val) r = val-1;
				}
				else if(l < val) l = val;
			}
			else {
				if(s[2].equals("Y")) {
					if(r > val) r = val;
				}
				else if(l <= val) l = val+1;
			}
		}

		if(l > r) System.out.println("Impossible");
		else {
			if(l == Integer.MIN_VALUE) System.out.println(r);
			else System.out.println(l);
		}
	}
}