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.*;
import java.io.*;

public class Main
{
	public static void main(String[] args)
	throws Exception
	{
		BufferedReader reader = new BufferedReader(
			new InputStreamReader(System.in));

		PrintWriter writer = new PrintWriter(System.out);
		StringTokenizer sz;

		int n = Integer.parseInt(reader.readLine());
		String op;
		int y;
		char ans;
		int min = /*Integer.MIN_VALUE WA */ (int)(-2*1e9) ;
		int max = /*Integer.MAX_VALUE WA */ (int)(2*1e9) ;

		for (int i=1;i <= n;++i)
		{
			sz = new StringTokenizer(reader.readLine());

			op = sz.nextToken();
			y = Integer.parseInt(sz.nextToken());
			ans = sz.nextToken().charAt(0);

			switch (op)
			{
				case ">=":

					if (ans == 'Y')
						min = Math.max(min, y);
					else
						max = Math.min(max, y - 1);

					break;

				case "<=":

					if (ans == 'Y')
						max = Math.min(max, y);
					else
						min = Math.max(min, y + 1);

					break;
				case ">":

					if (ans == 'Y')
						min = Math.max(min, y + 1);
					else
						max = Math.min(max, y);

					break;
				case "<":

					if (ans == 'Y')
						max = Math.min(max, y - 1);
					else
						min = Math.max(min, y);

			}
		}

		if (min > max)
			writer.println("Impossible");
		else
			writer.print(min); 

		writer.flush();
	}
}