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.InputStream;
import java.io.InputStreamReader;

public class A {
    
    static long max=(int)1e9;

    static StringBuilder sb=new StringBuilder();
    static void parse(String l, int[] here) {
        sb.setLength(0);
        int len=l.length(), j=0;
        for (int i=0; i<len; i++) {
            char c=l.charAt(i);
            if(c==' ') {
                here[j++]=Integer.parseInt(sb.toString());
                sb.setLength(0);
            } else {
                sb.append(c);
            }
        }
        if(sb.length()>0) {
            here[j++]=Integer.parseInt(sb.toString());
        }
    }
    
    static void run_stream(InputStream ins) throws IOException {
        BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
        int n=Integer.parseInt(br.readLine());
        long lo=-2*max, hi=2*max;
        for (int i=0; i<n; i++) {
            String[] SNA=br.readLine().split(" ");
            int m=Integer.parseInt(SNA[1]);
            boolean b=SNA[2].equals("Y");
            
            if(SNA[0].equals("<=")) {
                if(b) {
                    hi=Math.min(hi, m);
                } else {
                    lo=Math.max(lo, m+1);
                }
            } else if (SNA[0].equals("<")) {
                if(b) {
                    hi=Math.min(hi, m-1);
                } else {
                    lo=Math.max(lo, m);
                }
            } else if (SNA[0].equals(">=")) {
                if(b) {
                    lo=Math.max(lo, m);
                } else {
                    hi=Math.min(hi, m-1);
                }
            } else if (SNA[0].equals(">")) {
                if(b) {
                    lo=Math.max(lo, m+1);
                } else {
                    hi=Math.min(hi, m);
                }
            } 
        }
        
        if(lo>hi) {
            System.out.println("Impossible");
        } else {
            System.out.println(lo);
        }
    }

    public static void main(String[] args) throws IOException {
        run_stream(System.in);
    }

}