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.Arrays;
import java.util.BitSet;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.TreeSet;

public class Copy_2_of_CopyOfSolution {

    public static void main(final String[] args) throws NumberFormatException, IOException {
        final OutputStream outputStream = System.out;
        final PrintWriter out = new PrintWriter(outputStream);
        final InputReader in = new InputReader(System.in);
        final int n = in.nextInt();
        int left = -2 * 1000000000;
        int right = 2 * 1000000000;
        for (int i = 0; i < n; i++) {
            final String s = in.next();
            final int num = Integer.parseInt(in.next());
            final boolean yes = in.next().equals("Y") ? true : false;
            switch (s) {
                case ">":
                    if (yes) {
                        left = Math.max(num + 1, left);
                    } else {
                        right = Math.min(num, right);
                    }
                    break;
                case "<":
                    if (yes) {
                        right = Math.min(num - 1, right);
                    } else {
                        left = Math.max(num, left);
                    }
                    break;
                case ">=":
                    if (yes) {
                        left = Math.max(num, left);
                    } else {
                        right = Math.min(num - 1, right);
                    }
                    break;
                case "<=":
                    if (yes) {
                        right = Math.min(num, right);
                    } else {
                        left = Math.max(num + 1, left);
                    }
                    break;
            }
        }
        if ((left >= (-2 * 1000000000)) && (left <= (2 * 1000000000)) && (right >= (-2 * 1000000000))
                && (right <= (2 * 1000000000)) && (left <= right)) {
            out.println(left);
        } else {
            out.println("Impossible");
        }
        out.close();
    }

    private static void reverse(final double[] ken) {
        final int n = ken.length;
        for (int k = 0; k < (n / 2); k++) {
            final double temp = ken[k];
            ken[k] = ken[(n - k) - 1];
            ken[(n - k) - 1] = temp;
        }
    }

    private static double process(final double cost, final double inc, final double reach, double rate) {
        double t = 0;
        double t2 = reach / rate;
        double t3 = 0;
        do {
            t = t2;
            t3 += (cost / rate);
            rate += inc;
            t2 = t3 + (reach / rate);
            // System.out.println("Rate " + rate + " has time " + t2);
        } while (t2 < t);
        return t;
    }

    private static class InputReader {
        private final BufferedReader reader;
        private StringTokenizer s;

        public InputReader(final InputStream is) {
            final InputStreamReader in = new InputStreamReader(is);
            final BufferedReader reader = new BufferedReader(in);
            this.reader = reader;
        }

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

        public double nextDouble() {
            return Double.parseDouble(this.next());
        }

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

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

}