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.util.StringTokenizer;

/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/**
 *
 * @author Smith
 */
public class A {
 
    public static void main(String Args[]) throws IOException{
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        StringTokenizer st;
        int min = Integer.MIN_VALUE;
        int max = Integer.MAX_VALUE;
        int n = Integer.valueOf(br.readLine());
        for (int i=0;i<n;i++){
            st = new StringTokenizer(br.readLine());
            String tk = st.nextToken();
            int val = Integer.valueOf(st.nextToken());
            boolean b = st.nextToken().equals("Y");
            if (tk.equals(">=")){
                if (b){
                    min=Math.max(val,min);
                }else{
                    max=Math.min(val-1,max);
                }
            }else if (tk.equals(">")){
                if (b){
                    min=Math.max(val+1,min);
                }else{
                    max=Math.min(val,max);
                }
            }else if (tk.equals("<")){
                if (b){
                    max=Math.min(val-1,max);
                }else{
                    min=Math.max(val,min);
                }
            }else if (tk.equals("<=")){
                if (b){
                    max=Math.min(val,max);
                }else{
                    min=Math.max(val+1,min);
                }
            }
        }
        
        if (max>=min){
            System.out.println(Math.min(max,2000000000));
        }else{
            System.out.println("Impossible");
        }
    }
    
}