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.lang.*;
import java.math.*;
import java.io.*;
public class CodeForces {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int n = scan.nextInt(); String[] operations = new String[n];
        long[] val = new long[n];
        for(int i=0; i<n; i++) {
            operations[i] = scan.next();
            val[i] = scan.nextLong();
            String s = scan.next();
            scan.nextLine();
            if(s.equals("N")) {
                if(operations[i].equals(">="))
                    operations[i] = "<";
                else if(operations[i].equals("<="))
                    operations[i] = ">";
                else if(operations[i].equals(">"))
                    operations[i] = "<=";
                else if(operations[i].equals("<"))
                    operations[i] = ">=";
            }
        }
        long max = -1000000001;
        long min = 1000000001;
        for(int i=0; i<n; i++) {
            if(operations[i].equals(">="))
                if(val[i] > max)
                    max = val[i];
            if(operations[i].equals(">"))
                if(val[i]+1 > max)
                    max = val[i]+1;
            if(operations[i].equals("<="))
                if(val[i] < min)
                    min = val[i];
            if(operations[i].equals("<"))
                if(val[i]-1 < min)
                    min = val[i]-1;
        }
        if(max > min) 
            System.out.println("Impossible");
        else
            System.out.println(max);
    }
}