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.*;
import java.math.*;
public class Main {
    public static BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    public static StringTokenizer st = null;
    public static String nx() throws Exception {
        for (;st == null || !st.hasMoreTokens();){
            String line = in.readLine();
            if (line == null) return line;
            st = new StringTokenizer(line);
        }
        return st.nextToken();
    }
    public static int ni () throws Exception {return Integer.parseInt(nx());}
    public static PrintWriter out = new PrintWriter(System.out);
    public static void px(Object...objects) {
        System.out.println(Arrays.deepToString(objects));
    }
    public static void main(String[] args) throws Exception {
        s();
        out.flush();
    }
    public static void s() throws Exception {
        int max = 1_000_000_000 * 2 - 100;
        int min = 1_000_000_000 * 2 * -1 + 100;
        int n1 = ni();
        for (int i = 0 ; i  < n1; i++){
            String cmd = nx();
            int val = ni();
            boolean yes = nx().equals("Y");
            if (cmd.equals("<=")){
                if (yes){
                    max = Math.min(max, val);
                }
                else {
                    min = Math.max(min, val + 1);
                }
            }
            else if (cmd.equals(">=")){
                if (yes){
                    min = Math.max(min, val);
                    
                }
                else {
                    max = Math.min(max, val - 1);
                }
            }
            else if (cmd.equals("<")){
                if (yes){
                    max = Math.min(max, val - 1);
                    
                }
                else {
                    min = Math.max(min, val);
                }
            }
            else if (cmd.equals(">")){
                if (yes){
                    min = Math.max(min, val + 1);
                }
                else {
                    max = Math.min(max, val);
                }
            }
        }
        if (min <= max){
            out.println(min);
        }
        else {
            out.println("Impossible");
        }
    }
}