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.*;


public class Test {

    public static int MIN = -2000000000;
    public static int MAX = 2000000000;

    public static void TangMIN(int x) {
        if (MIN < x) {
            MIN = x;
        }
    }

    public static void GiamMAX(int x) {
        if (MAX > x) {
            MAX = x;
        }
    }

    public static void F(String dau, int x, char ans) {
        switch (dau) {
            case ">=":
                if (ans == 'Y') {
                    TangMIN(x);
                } else {
                    GiamMAX(x - 1);
                }   break;
            case "<=":
                if (ans == 'Y') {
                    GiamMAX(x);
                } else {
                    TangMIN(x + 1);
                }   break;
            case ">":
                if (ans == 'Y') {
                    TangMIN(x + 1);
                } else {
                    GiamMAX(x);
                }   break;
            case "<":
                if (ans == 'Y') {
                    GiamMAX(x - 1);
                } else {
                    TangMIN(x);
                }   break;
        }
    }
   
    public static void main(String[] args) {
        String s;
        int x;
        char ans;
        int n;
        Scanner scan = new Scanner(System.in);
        n = scan.nextInt();
        for (int i = 0; i < n; i++) {
            s = scan.next();
            x = scan.nextInt();
            ans = scan.next().charAt(0);
            F(s,x,ans);
        }
        
        if(MIN <= MAX)
        System.out.println(MIN);
        else System.out.println("Impossible");
    }
    
}