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.util.*;
import java.lang.*;
import java.io.*;
import java.math.*;
import java.util.concurrent.*;

public class Main {
    //---------------------------------------------------------------------------

    public static void main(String[] args) throws Exception {
        InputReader in = new InputReader(System.in);
        PrintWriter out = new PrintWriter(System.out);
        //-----------------------------------------------------------------------
        int n = in.nextInt();
        int l = -2000000001;
        int r = 2000000001;
        while (n > 0) {
            String s = in.next();
            int x = in.nextInt();
            String a = in.next();
            switch (s) {
                case ">": {
                    if (a.equals("Y")) {
                        l = Math.max(l, x);
                    } else {
                        r = Math.min(r, x + 1);
                    }
                    break;
                }
                case "<": {
                    if (a.equals("N")) {
                        l = Math.max(l, x - 1);
                    } else {
                        r = Math.min(r, x);
                    }
                    break;
                }
                case ">=": {
                    if (a.equals("Y")) {
                        l = Math.max(l, x - 1);
                    } else {
                        r = Math.min(r, x);
                    }
                    break;
                }
                case "<=": {
                    if (a.equals("N")) {
                        l = Math.max(l, x);
                    } else {
                        r = Math.min(r, x + 1);
                    }
                    break;
                }
            }
            n--;
        }
        if (l >= r - 1) {
            out.println("Impossible");
        } else {
            out.println(l + 1);
        }
        //-----------------------------------------------------------------------
        out.close();
    }

    //---------------------------------------------------------------------------
    static void shuffleArray(int[] ar) {
        Random rnd = ThreadLocalRandom.current();
        for (int i = ar.length - 1; i > 0; i--) {
            int index = rnd.nextInt(i + 1);
            int a = ar[index];
            ar[index] = ar[i];
            ar[i] = a;
        }
    }

    static class Pair<F, S> implements Comparable<Pair<F, S>> {

        F first;
        S second;

        public Pair() {

        }

        public Pair(F f, S s) {
            this.first = f;
            this.second = s;
        }

        @Override public boolean equals(Object o) {
            Pair<F, S> p = (Pair<F, S>) o;
            if (first.equals(p.first) && second.equals(p.second)) {
                return true;
            }
            return false;
        }

        public int compareTo(Pair<F, S> p) {
            int ret = ((Comparable<F>) first).compareTo(p.first);
            if (ret == 0) {
                ret = ((Comparable<S>) second).compareTo(p.second);
            }
            return ret;
        }
    }

    static class BitMask {
        private int mask;

        public BitMask() {
            mask = 0;
        }

        public BitMask(BitMask b) {
            mask = b.getMask();
        }

        public BitMask(int i) {
            mask = i;
        }

        public int getMask() {
            return mask;
        }

        public void setMask(int i) {
            mask = i;
        }

        public int get(int i) {
            return (mask >> i) & 1;
        }

        public void set(int i, int v) {
            if (v == 0) {
                mask = mask & ~(1 << i);
            } else {
                mask = mask | (1 << i);
            }
        }

        public void set(int v) {
            for (int i = 0; i < 32; i++) {
                set(i, v);
            }
        }

        public void flip(int i) {
            mask = mask ^ (1 << i);
        }

        public void flip() {
            for (int i = 0; i < 31; i++) {
                flip(i);
            }
        }

        public int count() {
            int ret = 0;
            for (int i = 0; i < 32; i++) {
                if (get(i) == 1) {
                    ret++;
                }
            }
            return ret;
        }

        public static int grayCode(int i) {
            return i ^ (i >> 1);
        }
    }

    static class InputReader {

        public BufferedReader reader;
        public StringTokenizer tokenizer;

        public InputReader(InputStream stream) {
            reader = new BufferedReader(new InputStreamReader(stream), 32768);
            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 long nextLong() {
            return Long.parseLong(next());
        }

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

        public char[] nextCharArray() {
            return next().toCharArray();
        }

        public boolean hasNext() {
            while (tokenizer == null || !tokenizer.hasMoreTokens()) {
                try {
                    String s = reader.readLine();
                    if (s == null) {
                        return false;
                    }
                    tokenizer = new StringTokenizer(s);
                } catch (IOException e) {
                    throw new RuntimeException(e);
                }
            }
            return true;
        }

        public void skipLine() {
            try {
                tokenizer = null;
                reader.readLine();
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
    }
}