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.*;
import java.util.*;

import static java.lang.Math.*;

public class CF416A_GuessANumber extends PrintWriter {
    public void solve() throws IOException {
        int n = readInt();
        int hi =  2 * 1000 * 1000 * 1000;
        int lo = -hi;
        for (int i = 0; i < n; i++) {
            String op = read();
            Integer x = readInt();
            String yn = read();

            if(op.equals(">") && yn.equals("Y") || op.equals("<=") && yn.equals("N"))
                lo = max(lo, x + 1);
            if(op.equals(">=") && yn.equals("Y") || op.equals("<") && yn.equals("N"))
                lo = max(lo, x);
            if(op.equals("<") && yn.equals("Y") || op.equals(">=") && yn.equals("N"))
                hi = min(hi, x - 1);
            if(op.equals("<=") && yn.equals("Y") || op.equals(">") && yn.equals("N"))
                hi = min(hi, x);
        }

        println(lo <= hi ? lo : "Impossible");
    }

    BufferedReader in;
    StringTokenizer stok;

    public void run() {
        try {
            solve();
            close();
        } catch (Exception e) {
            e.printStackTrace();
            System.exit(abs(-1));
        }
    }

    CF416A_GuessANumber() throws IOException {
        super(System.out);
        in = new BufferedReader(new InputStreamReader(System.in));
    }

    public static void main(String[] args) throws IOException {
        try {
            Locale.setDefault(Locale.US);
        } catch (Exception ignored) {
        }
        new CF416A_GuessANumber().run();
    }

    String read() throws IOException {
        while (stok == null || !stok.hasMoreTokens()) {
            String s = in.readLine();
            if (s == null) {
                return null;
            }
            stok = new StringTokenizer(s);
        }
        return stok.nextToken();
    }

    int readInt() throws IOException {
        return Integer.parseInt(read());
    }

    long readLong() throws IOException {
        return Long.parseLong(read());
    }

    double readDouble() throws IOException {
        return Double.parseDouble(read());
    }

    int[] readIntArray(int len) throws IOException {
        int[] a = new int[len];
        for (int i = 0; i < len; i++) {
            a[i] = readInt();
        }
        return a;
    }

    <T> List<T>[] createAdjacencyList(int countVertex) {
        List<T>[] res = new List[countVertex];
        for (int i = 0; i < countVertex; i++) {
            res[i] = new ArrayList<T>();
        }
        return res;
    }
}