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:
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;

/**
 *
 * @author Darkhan
 */
public class task {
    public static void main(String[] args) throws IOException{
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
        int n = Integer.parseInt(in.readLine());
        String[] s;
        long x,l = -2000000000, r = 2000000000;
        while (n > 0){
            s = in.readLine().split(" ");
            switch (s[0]){
                case ">":
                    x = Long.parseLong(s[1]);
                    if (s[2].equals("Y") && l < x + 1){
                        l = x + 1;
                    }
                    else if (s[2].equals("N") && r > x){
                        r = x;
                    }
                    break;
                case "<":
                    x = Long.parseLong(s[1]);
                    if (s[2].equals("Y") && r > x - 1){
                        r = x - 1;
                    }
                    else if (s[2].equals("N") && l < x){
                        l = x;
                    }
                    break;
                case ">=":
                    x = Long.parseLong(s[1]);
                    if (s[2].equals("Y") && l < x){
                        l = x;
                    }
                    else if (s[2].equals("N") && r > x - 1){
                        r = x - 1;
                    }
                    break;
                case "<=":
                    x = Long.parseLong(s[1]);
                    if (s[2].equals("Y") && r > x){
                        r = x;
                    }
                    else if (s[2].equals("N") && l < x + 1){
                        l = x + 1;
                    }
                    break;
                default:
                    break;
            }
            n--;
        }
        in.close();
        if (l <= r) out.println(l);
        else out.println("Impossible");
        out.close();
    }
}