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;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.StringTokenizer;

public class First {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        TaskA solver = new TaskA();
        solver.solve(1, in, out);
        out.close();
    }
}

class TaskA {
    public void solve(int testNumber, InputReader in, PrintWriter out) {
        int n = in.nextInt();
        String[] input = new String[n];
        for (int i = 0; i < n; i++) {
            input[i] = in.nextLine();
        }
        
        List <Integer> geList = new ArrayList <> ();
        List <Integer> leList = new ArrayList <> ();
        
        for (int index = 0; index < input.length; index++) {
            String[] arr = input[index].split(" ");
            int value = Integer.valueOf(arr[1]);
            if (arr[2].equals("Y")) {
                if (arr[0].equals(">=")) {
                    geList.add(value);
                }
                if (arr[0].equals(">")) {
                    geList.add(value + 1);
                }
                if (arr[0].equals("<=")) {
                    leList.add(value);
                }
                if (arr[0].equals("<")) {
                    leList.add(value - 1);
                }
            } else {
                if (arr[0].equals(">=")) {
                    leList.add(value - 1);
                }
                if (arr[0].equals(">")) {
                    leList.add(value);
                }
                if (arr[0].equals("<=")) {
                    geList.add(value + 1);
                }
                if (arr[0].equals("<")) {
                    geList.add(value);
                }
            }
        }
        int geNum = Integer.MIN_VALUE;
        int leNum = Integer.MAX_VALUE;
        
        for (int i = 0; i < leList.size(); i++) {
            leNum = Math.min(leNum, leList.get(i));
        }
        for (int i = 0; i < geList.size(); i++) {
            geNum = Math.max(geNum, geList.get(i));
        }
        
        if (geNum != Integer.MIN_VALUE && leNum != Integer.MAX_VALUE && geNum <= leNum) {
            out.println(geNum);
        } else if (geNum != Integer.MIN_VALUE && leNum == Integer.MAX_VALUE) {
            out.println(geNum);
        } else if (geNum == Integer.MIN_VALUE && leNum != Integer.MAX_VALUE) {
            out.println(leNum);
        } else {
            out.println("Impossible");
        }
    }
}

class InputReader {
    private BufferedReader reader;
    private StringTokenizer tokenizer;

    public InputReader(InputStream stream) {
        reader = new BufferedReader(new InputStreamReader(stream));
        tokenizer = null;
    }

    public String next() {
        while (tokenizer == null || !tokenizer.hasMoreTokens()) {
            try {
                tokenizer = new StringTokenizer(reader.readLine());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return tokenizer.nextToken();
    }

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

    public String nextLine() {
        String inputLine = "";
        try {
            inputLine = reader.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return inputLine;
    }
}