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;

/**
 *
 * @author mina
 */
public class A {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int max = 2000000000, min = -2000000000;
        for (int i = 0; i < n; i++) {
            String sign = sc.next();
            int x = sc.nextInt();
            String inv = sc.next().toLowerCase();

            switch (sign) {

                case ">":
                    if ("y".equals(inv)) {
                        if (x + 1 > min) {
                            min = x + 1;
                        }
                    } else if ("n".equals(inv)) {
                        if (x < max) {
                            max = x;
                        }
                    }
                    break;
                case ">=":
                    if ("y".equals(inv)) {
                        if (x > min) {
                            min = x;
                        }
                    } else if ("n".equals(inv)) {
                        if (x - 1 < max) {
                            max = x - 1;
                        }
                    }
                    break;
                case "<":
                    if ("y".equals(inv)) {
                        if (x - 1 < max) {
                            max = x - 1;
                        }
                    } else if ("n".equals(inv)) {
                        if (x > min) {
                            min = x;
                        }
                    }
                    break;
                case "<=":
                    if ("y".equals(inv)) {
                        if (x < max) {
                            max = x;
                        }
                    } else if ("n".equals(inv)) {
                        if (x + 1 > min) {
                            min = x + 1;
                        }
                    }
                    break;
            }

        }
        if (max >= min) {
            System.out.print(min);
        } else {
            System.out.print("Impossible");

        }
    }

}