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.*;
import java.io.*;

public class Main{

  BufferedReader in;
  StringTokenizer str = null;
  PrintWriter out;

  private String next() throws Exception{
    while(str == null || !str.hasMoreElements())
      str = new StringTokenizer(in.readLine());
    return str.nextToken();
  }

  private int nextInt() throws Exception{
    return Integer.parseInt(next());
  }

  final static int oo = 2000000000;

  public void run() throws Exception{
    in = new BufferedReader(new InputStreamReader(System.in)); 
    out = new PrintWriter(System.out);
    int n = nextInt();

    int left = -oo;
    int right = oo;
    for(int i=0;i<n;i++){
      String op = next();
      int b = nextInt();
      String ans = next();
      if (ans.equals("N")){
        if (op.equals("<")) op = ">=";
        else if (op.equals(">")) op = "<=";
        else if (op.equals("<=")) op = ">";
        else op = "<";
      }
      if (op.equals("<")){
        b--;
        right = Math.min(right, b);
      }else if (op.equals(">")){
        b++;
        left = Math.max(b, left);
      }else if (op.equals("<=")){
        right = Math.min(right, b);
      }else{
        left = Math.max(left, b);
      }
    }

    if (left > right){
      out.println("Impossible");
    }else{
      out.println(left);
    }

    out.close();
  }
 
  public static void main(String args[]) throws Exception{
    new Main().run();  
  }
}