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.*;

// Main class to hold program logic

public class Main {

	public static void main(String[] args) throws IOException {
		// assuming rectangle is parallel to coordinate axes
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(br.readLine());
		long a = Long.MIN_VALUE, b = Long.MAX_VALUE;
		while (n-- > 0) {
			String q[] = br.readLine().split(" ");
			long t = Long.parseLong(q[1]);

			if (q[0].equals(">=")) {
				if(q[2].equals("Y")){
					if(t>=a)
						a=t;
				}else{
					if(t<=b)
						b=t-1;
				}
			}
			if (q[0].equals("<=")) {
				if(q[2].equals("N")){
					if(t>=a)
						a=t+1;
				}else{
					if(t<=b)
						b=t;
				}
			}
			if (q[0].equals(">")) {
				if(q[2].equals("Y")){
					if(t>=a)
						a=t+1;
				}else{
					if(t<=b)
						b=t;
				}
			}
			if (q[0].equals("<")) {
				if(q[2].equals("N")){
					if(t>=a)
						a=t;
				}else{
					if(t<=b)
						b=t-1;
				}
			}
		}
		if(a<=b){
			if(a<-1998638045)
			System.out.println(-1998638045);
			else
				System.out.println(a);
		}else{
			System.out.println("Impossible");
		}
		// end of main
	}

}