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.lang.Long;

public class main {

	public static void main(String[] args) {

		Scanner input = new Scanner(System.in);

		long lower = (-1) * 1000000010L, upper = 1000000010, n, num;
		String ans;
		String equation;

		n = input.nextInt();
		input.nextLine();

		for (int i = 0; i < n; i++) {
			equation = input.next();
			num = input.nextInt();
			ans = input.next();
			input.nextLine();

			if (equation.equals(">")) {
				if (ans.equals("Y")) {
					if (num >= lower) {
						lower = num + 1;
					}

				} else {
					if (num < upper) {
						upper = num;
					}

				}

			} else if (equation.equals("<")) {
				if (ans.equals("Y")) {
					if (num <= upper) {
						upper = num - 1;
					}

				} else {
					if (num > lower) {
						lower = num;
					}

				}
			} else if (equation.equals(">=")) {
				if (ans.equals("Y")) {
					if (num > lower) {
						lower = num;
					}

				} else {
					if (num < upper) {
						upper = num - 1;
					}

				}
			} else if (equation.equals("<=")) {
				if (ans.equals("Y")) {
					if (num < upper) {
						upper = num;
					}

				} else {
					if (num > lower) {
						lower = num + 1;
					}
				}
			}

		}
		if (upper < lower) {
			System.out.print("Impossible");
		} else {
			System.out.print((lower + upper) / 2);
		}

		input.close();
	}

}