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.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.io.BufferedOutputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.InputMismatchException;

public class Main {

    public static void main(String[] args) {
        if (args.length > 0 && args[0].toLowerCase().equals("local")) {
            try {
                System.setIn(new FileInputStream("input.txt"));
                System.setOut(new PrintStream(new File("output.txt")));
            } catch (IOException exc) {
            }
        }
        Task task = new Task();
        task.solve();
    }

    public static class Task {
        static final long MOD = (long) 1e9 + 7;
        static final PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out));

        public void solve() {
            try {
                Scan sc = new Scan();
                int n = (int) sc.scanLong();
                int l = -2000000000;
                int r = 2000000000;
                while (n-- > 0) {
                    String op = sc.scanString();
                    int val = (int) sc.scanLong();
                    String verdict = sc.scanString();
                    if (verdict.equals("Y")) {
                        if (op.equals(">=")) {
                            if (val > r) {
                                out.println("Impossible");
                                return;
                            }
                            l = Math.max(l, val);
                        } else if (op.equals(">")) {
                            if (val + 1 > r) {
                                out.println("Impossible");
                                return;
                            }
                            l = Math.max(l, val + 1);
                        } else if (op.equals("<=")) {
                            if (val < l) {
                                out.println("Impossible");
                                return;
                            }
                            r = Math.min(r, val);
                        } else {
                            if (val - 1 < l) {
                                out.println("Impossible");
                                return;
                            }
                            r = Math.min(r, val - 1);
                        }
                    } else {
                        if (op.equals(">=")) {
                            if (val - 1 < l) {
                                out.println("Impossible");
                                return;
                            }
                            r = Math.min(r, val - 1);
                        } else if (op.equals(">")) {
                            if (val < l) {
                                out.println("Impossible");
                                return;
                            }
                            r = Math.min(r, val);
                        } else if (op.equals("<=")) {
                            if (val + 1 > r) {
                                out.println("Impossible");
                                return;
                            }
                            l = Math.max(l, val + 1);
                        } else {
                            if (val > r) {
                                out.println("Impossible");
                                return;
                            }
                            l = Math.max(l, val);
                        }
                    }
                }
                out.println(l);
            } finally {
                out.close();
            }
        }

        private void debug(Object... x) {
            StringBuilder sb = new StringBuilder();
            for (Object o : x)
                sb.append(String.valueOf(o)).append(" ");
            out.println(sb);
        }
    }

    public static class Scan {
        private byte[] buf = new byte[1024];
        private int index;
        private InputStream in;
        private int total;

        public Scan() {
            in = System.in;
        }

        public int scan() {
            if (total < 0)
                throw new InputMismatchException();
            if (index >= total) {
                index = 0;
                try {
                    total = in.read(buf);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
                if (total <= 0)
                    return -1;
            }
            return buf[index++];
        }

        public long scanLong() {
            long integer = 0;
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            int neg = 1;
            if (n == '-') {
                neg = -1;
                n = scan();
            }
            while (!isWhiteSpace(n)) {
                if (n >= '0' && n <= '9') {
                    integer *= 10;
                    integer += n - '0';
                    n = scan();
                } else
                    throw new InputMismatchException();
            }
            return neg * integer;
        }

        public double scanDouble() {
            double doub = 0;
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            int neg = 1;
            if (n == '-') {
                neg = -1;
                n = scan();
            }
            while (!isWhiteSpace(n) && n != '.') {
                if (n >= '0' && n <= '9') {
                    doub *= 10;
                    doub += n - '0';
                    n = scan();
                } else
                    throw new InputMismatchException();
            }
            if (n == '.') {
                n = scan();
                double temp = 1;
                while (!isWhiteSpace(n)) {
                    if (n >= '0' && n <= '9') {
                        temp /= 10;
                        doub += (n - '0') * temp;
                        n = scan();
                    } else
                        throw new InputMismatchException();
                }
            }
            return doub * neg;
        }

        public String scanString() {
            StringBuilder sb = new StringBuilder();
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            while (!isWhiteSpace(n)) {
                sb.append((char) n);
                n = scan();
            }
            return sb.toString();
        }

        public char scanChar() {
            int n = scan();
            while (isWhiteSpace(n))
                n = scan();
            return (char) n;
        }

        private boolean isWhiteSpace(int n) {
            if (n == ' ' || n == '\n' || n == '\r' || n == '\t' || n == -1)
                return true;
            return false;
        }
    }
}