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.io.*;
import java.math.*;

public class A {
    void solve() {
        int l = -(int)2e9, r = (int)2e9;
        int n = sc.nextInt();
        for (int i = 0; i < n; i++) {
            String s = sc.nextStr();
            int x = sc.nextInt();
            String s2 = sc.nextStr();
            boolean ok = s2.equals("Y");
            if (!ok) {
                char c = s.charAt(0);
                c = (char)((int)'>' + (int)'<' - (int)c);
                if (s.length() == 1) {
                    s = c + "=";    
                } else {
                    s = c + "";
                }
            }
           // out.println(s);
            if (s.charAt(0) == '>') {
                if (s.length() == 1) {
                    x++;
                }
                l = max(x, l);
            } else {
                if (s.length() == 1) {
                    x--;
                }
                r = min(r, x);
            }
        }
        if (l > r) {
            out.print("Impossible");
        } else {
            out.print(l);
        }
    }
    int min (int a, int b) {
        return a < b ? a : b;
    }
    int max (int a, int b) {
        return a > b ? a : b;
    }
    FastScanner sc;
    PrintWriter out;

    public static void main(String[] args) {
        (new A()).run();
    }

    void run() {
        sc = new FastScanner();
        out = new PrintWriter(System.out);
        solve();
        out.flush();
    }

    public static class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner(String s) {
            try {
                br = new BufferedReader(new FileReader(s));
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }

        public FastScanner() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String nextToken() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

        int nextInt() {
            return Integer.parseInt(nextToken());
        }

        long nextLong() {
            return Long.parseLong(nextToken());
        }

        double nextDouble() {
            return Double.parseDouble(nextToken());
        }

        String nextStr() {
            return nextToken();
        }
    }
}