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.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class A {

    
    public static void main(String[] args) throws IOException {
        Scanner sc = new Scanner(System.in);
        PrintWriter out = new PrintWriter(System.out);
        
        int n = sc.nextInt();
        Range r = new Range(-(int)2e9, (int)2e9);
        boolean possible = true;
        while(n-->0)
        {
            String op = sc.next();
            int x = sc.nextInt();
            String ans = sc.next();
            if(op.equals(">=") && ans.equals("Y") || op.equals("<") && ans.equals("N"))
                r = r.intersect(new Range(x, (int)2e9));
            else
                if(op.equals("<=") && ans.equals("Y") || op.equals(">") && ans.equals("N"))
                    r = r.intersect(new Range(-(int)2e9, x));
                else
                    if(op.equals(">") && ans.equals("Y") || op.equals("<=") && ans.equals("N"))
                        r = r.intersect(new Range(x + 1, (int)2e9));
                    else
                        r = r.intersect(new Range(-(int)2e9, x - 1));
            if(r == null)
            {
                possible = false;
                break;
            }
        }
        if(possible)
            out.println(r.a);
        else
            out.println("Impossible");
        out.flush();
        out.close();
    }
    
    static class Range{
        int a, b;
        
        Range(int x, int y) { a = x; b = y; }
        
        Range intersect(Range r)
        {
            if(a > r.b || r.a > b)
                return null;
            return new Range(Math.max(a, r.a), Math.min(b, r.b));
        }
    }
    
    static class Scanner 
    {
        StringTokenizer st;
        BufferedReader br;

        public Scanner(FileReader fileReader) throws FileNotFoundException{ br = new BufferedReader(fileReader);}

        public Scanner(InputStream s) throws FileNotFoundException{ br = new BufferedReader(new InputStreamReader(s));}

        public String next() throws IOException 
        {
            while (st == null || !st.hasMoreTokens()) 
                st = new StringTokenizer(br.readLine());
            return st.nextToken();
        }

        public double nextDouble() throws IOException
        {
            String x = next();
            StringBuilder sb = new StringBuilder("0");
            double res = 0, f = 1;
            boolean dec = false, neg = false;
            int start = 0;
            if(x.charAt(0) == '-')
            {
                neg = true;
                start++;
            }
            for(int i = start; i < x.length(); i++)
                if(x.charAt(i) == '.')
                {
                    res = Long.parseLong(sb.toString());
                    sb = new StringBuilder("0");
                    dec = true;
                }
                else
                {
                    sb.append(x.charAt(i));
                    if(dec)
                        f *= 10;
                }
            res += Long.parseLong(sb.toString()) / f;
            return res * (neg?-1:1);
        }


        public int nextInt() throws IOException {return Integer.parseInt(next());}

        public long nextLong() throws IOException {return Long.parseLong(next());}

        public String nextLine() throws IOException {return br.readLine();}

        public boolean ready() throws IOException {return br.ready(); }


    }

}