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.Scanner;


public class A {
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		long low = (long)-2e9;
		long high =(long) 2e9;
		while(N-->0){
			String d = sc.next();
			long num = sc.nextInt();
			String ans = sc.next();
			int dir = 1;
			if(d.contains("<"))dir = -1;
			
			
			boolean bad=ans.equals("N"); 
			if(bad){
				if(dir==1)dir=-1;
				else dir = 1;
			}
			
			if((!bad&&!d.contains("="))||(bad&&d.contains("="))){
			//	System.out.println("HA");
				num+=dir;
			}
		//	System.out.println(num+" D "+dir);
			
			if(dir==1){
				low = Math.max(low,num);
			}
			else {
				high = Math.min(high, num);
			}
		//	System.out.println("L "+low+" H "+high);
		}
		if(low>high){
			System.out.println("Impossible");
		}
		else{
			System.out.println(low);
		}

	}

}