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;

/*
 * 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.
 */
/**
 *
 * @author KHALED
 */
public class Guessanumber {
    public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long from = -2000000000L;
    long to = 2000000000L;
    int n = sc.nextInt();
    for (int i = 0; i < n; i++) {
      String operator = sc.next();
      long number = sc.nextLong();
      String answer = sc.next();
      if (operator.equals(">=")) {
        if (answer.equals("Y")) {
          from = Math.max(from, number);
        } else {
          to = Math.min(to, number - 1);
        }
      } else if (operator.equals(">")) {
        if (answer.equals("Y")) {
          from = Math.max(from, number + 1);
        } else {
          to = Math.min(to, number);
        }
      } else if (operator.equals("<=")) {
        if (answer.equals("Y")) {
          to = Math.min(to, number);
        } else {
          from = Math.max(from, number + 1);
        }
      } else if (operator.equals("<")) {
        if (answer.equals("Y")) {
          to = Math.min(to, number - 1);
        } else {
          from = Math.max(from, number);
        }
      }
    }
    if (from > to) {
      System.out.println("Impossible");
    } else {
        System.out.println(from);
//        Scanner scan=new Scanner(System.in);
//        int n=scan.nextInt();
//        int output=0;
//        int count=0;
//        int g=Integer.MIN_VALUE;
//        int l=Integer.MAX_VALUE;
//        for (int i = 0; i < n; i++) 
//        {
//            String k=scan.next();
//            int h=scan.nextInt();
//            String s=scan.next();
//            if(k.compareTo(">")==0)
//            {
//                if(s.compareTo("Y")==0)
//                {
//                    if(output<h+1)
//                        output=h+1;
//                }
//                else
//                {
//                    output-=h;
//                }
//            }
//            else if(k.compareTo(">=")==0)
//            {
//                if(s.compareTo("Y")==0)
//                {
//                    if(output<h+1)
//                        output=h;
//                }
//                else
//                {
//                    output-=h;
//                }
//            }
//            else if(k.compareTo("<")==0)
//            {
//                if(s.compareTo("Y")==0)
//                {
//                    if(output>h+1)
//                        output=h-1;
//                }
//                else
//                {
//                    output+=h;
//                }
//            }
//            else if(k.compareTo("<=")==0)
//            {
//                if(s.compareTo("Y")==0)
//                {
//                    if(output>h)
//                        output=h;
//                }
//                else
//                {
//                    output+=h;
//                }
//            }
//        }
//        if(g>l)
//            System.out.println("Impossible");
//        else
//        {
//            System.out.println(output);
//        }
    }}
}