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.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author Vishal Burman
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        AGuessANumber solver = new AGuessANumber();
        solver.solve(1, in, out);
        out.close();
    }

    static class AGuessANumber {
        public void solve(int testNumber, InputReader in, PrintWriter out) {
            int n = Integer.parseInt(in.readLine());
            int lhs = -2 * 1000000000;
            int rhs = 2 * 1000000000;
            for (int i = 0; i < n; i++) {
                String str[] = in.readLine().split(" ");
                if (str[0].equals(">") && str[2].equals("Y")) {
                    lhs = Math.max(lhs, Integer.parseInt(str[1]) + 1);
                }

                if (str[0].equals(">") && str[2].equals("N"))
                    rhs = Math.min(rhs, Integer.parseInt(str[1]));

                if (str[0].equals(">=") && str[2].equals("Y"))
                    lhs = Math.max(lhs, Integer.parseInt(str[1]));

                if (str[0].equals(">=") && str[2].equals("N"))
                    rhs = Math.min(rhs, Integer.parseInt(str[1]) - 1);

                if (str[0].equals("<") && str[2].equals("Y"))
                    rhs = Math.min(rhs, Integer.parseInt(str[1]) - 1);

                if (str[0].equals("<") && str[2].equals("N"))
                    lhs = Math.max(lhs, Integer.parseInt(str[1]));

                if (str[0].equals("<=") && str[2].equals("Y"))
                    rhs = Math.min(rhs, Integer.parseInt(str[1]));

                if (str[0].equals("<=") && str[2].equals("N"))
                    lhs = Math.max(lhs, Integer.parseInt(str[1]) + 1);

            }
            if (rhs < lhs)
                out.println("Impossible");
            else {
                out.println(lhs);
            }
        }

    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        public int read() {
            if (numChars == -1) {
                throw new InputMismatchException();
            }
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar++];
        }

        private String readLine0() {
            StringBuilder buf = new StringBuilder();
            int c = read();
            while (c != '\n' && c != -1) {
                if (c != '\r') {
                    buf.appendCodePoint(c);
                }
                c = read();
            }
            return buf.toString();
        }

        public String readLine() {
            String s = readLine0();
            while (s.trim().length() == 0) {
                s = readLine0();
            }
            return s;
        }

    }
}