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.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class A {
	public static void main(String[] args) throws IOException {
		BufferedReader br  = new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(br.readLine());
		String[] s = new String[n];
		for(int i = 0; i< n;i++) {
			s[i] = br.readLine();
		}

		long min = -2000000000, max = 2000000000;
		boolean flag = true;
			for (int j = 0; j < s.length; j++) {
				if(s[j].split(" ")[0].equals(">=")) {
					if(s[j].split(" ")[2].equals("Y")) {
						min=Math.max(min, Long.parseLong(s[j].split(" ")[1]));
					} else {
						max=Math.min(max, Long.parseLong(s[j].split(" ")[1])-1);
					}
				} else if(s[j].split(" ")[0].equals("<=")) {
					if(s[j].split(" ")[2].equals("Y")) {
						max=Math.min(max, Long.parseLong(s[j].split(" ")[1]));
					} else {
						min=Math.max(min, Long.parseLong(s[j].split(" ")[1])+1);
					}
				} else if(s[j].split(" ")[0].equals(">")) {
					if(s[j].split(" ")[2].equals("Y")) {
						min=Math.max(min, Long.parseLong(s[j].split(" ")[1])+1);
					} else {
						max=Math.min(max, Long.parseLong(s[j].split(" ")[1]));
					}
				} else {
					if(s[j].split(" ")[2].equals("Y")) {
						max=Math.min(max, Long.parseLong(s[j].split(" ")[1])-1);
					} else {
						min=Math.max(min, Long.parseLong(s[j].split(" ")[1]));
					}
				}
			}
		
		if(min>max) {
			System.out.println("Impossible");
		} else {
			System.out.println(min);
		}
	}
}