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;

public class A {

    public static void main(String[] args) {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        try {
            String s = br.readLine();
            int n = Integer.parseInt(s);
            int r = 2000000000;
            int l = -r;
            String[] ss;
            for (int i = 0; i < n; i++) {
                s = br.readLine();
                ss = s.split(" ");
                int a = Integer.parseInt(ss[1]);
                if (("<".equals(ss[0]) && "N".equals(ss[2])) || (">=".equals(ss[0]) && "Y".equals(ss[2]))) {
                    if (a > l) {
                        l = a;
                    }
                } else if (("<".equals(ss[0]) && "Y".equals(ss[2])) || (">=".equals(ss[0]) && "N".equals(ss[2]))) {
                    if (a - 1 < r) {
                        r = a - 1;
                    }
                } else if ((">".equals(ss[0]) && "N".equals(ss[2])) || ("<=".equals(ss[0]) && "Y".equals(ss[2]))) {
                    if (a < r) {
                        r = a;
                    }
                } else if ((">".equals(ss[0]) && "Y".equals(ss[2])) || ("<=".equals(ss[0]) && "N".equals(ss[2]))) {
                    if (a + 1 > l) {
                        l = a + 1;
                    }
                }
            }
            if (l > r) {
                System.out.println("Impossible");
            } else {
                System.out.println(l);
            }
        } catch (IOException ex) {
        } finally {
            try {
                br.close();
            } catch (IOException ex) {
            }
        }
    }
}