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;
import java.math.BigInteger;
import java.util.HashSet;

public class Main3 {
	
	public static void main(String[] args) throws NumberFormatException, IOException {
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		int n = Integer.parseInt(br.readLine());
		int min = 2*-1000000000;
		int max = 2*1000000000;
		
		for (int i = 0; i < n; i++) {
			String [] temp = br.readLine().split(" ");
			int x = Integer.parseInt(temp[1]);
			if(temp[2].equals("Y")){
				switch(temp[0]){
				case "<": max = (Integer.parseInt(temp[1])-1< max )? Integer.parseInt(temp[1])-1:max;break;
				case ">": min = (Integer.parseInt(temp[1])+1 >min)?Integer.parseInt(temp[1])+1:min ;break;
				case ">=": min = (Integer.parseInt(temp[1]) >min)?Integer.parseInt(temp[1]):min;break;
				case "<=": max = (Integer.parseInt(temp[1])<max )? Integer.parseInt(temp[1]):max;break;
				}
			}else{
				switch(temp[0]){
				case "<": min = (Integer.parseInt(temp[1]) >min)?Integer.parseInt(temp[1]):min;break;
				case ">": max = (Integer.parseInt(temp[1]) <max )? Integer.parseInt(temp[1]):max ;break;
				case ">=": max = (Integer.parseInt(temp[1])-1<max )? Integer.parseInt(temp[1])-1:max;break;
				case "<=":min =  (Integer.parseInt(temp[1])+1 >min)?Integer.parseInt(temp[1])+1:min;break;
				}
			}
		}
		if(min <= max && min >= 2*-1000000000 && max <= 2*1000000000){
			System.out.println(min);
		}else{
			System.out.println("Impossible");
		}
	}
	
}