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();
		int upper = 1000000010;
		int lower = -1000000010;
		boolean flag = true;
		for(int i=0;i<n;i++) {
			String sign = sc.next();
			int num = sc.nextInt();
			String ans = sc.next();
			int signnum = 0;
			switch (sign) {
			case ">":
				signnum = 0;
				break;
			case "<":
				signnum = 1;
				break;
			case "<=":
				signnum = 2;
				break;
			case ">=":
				signnum = 3;
				break;
			}
			if (ans.equals("N")) {
				signnum = (signnum + 2) % 4;
			}
			switch (signnum) {
			case 0:
				lower = Math.max(lower, num + 1);
				break;
			case 1:
				upper = Math.min(upper,num - 1);
				break;
			case 2:
				upper = Math.min(upper,num);
				break;
			case 3:
				lower = Math.max(lower,num);
				break;
			}
			if (lower > upper) {
				flag = false;
				break;
			}
		}
		if (flag) {
			System.out.println(lower);
		}else{
			System.out.println("Impossible");
		}
	}

}