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.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.util.StringTokenizer;

public class A {
	static BufferedReader in;
	static StringTokenizer st;
	static PrintWriter out;
	public static void main(String[] args) throws IOException {
		begin();
		solve();
		end();
	}
	private static void end() {
		out.close();
	}
	private static void solve() throws IOException {
		int n = nextInt();
		int left = -(int) (2*1e9);
		int right = (int) (2*1e9);
		for (int i = 0; i < n; i++) {
			String s = next();
			int x = nextInt();
			char A = next().charAt(0);
			if (s.equals(">=")){
				if ( A == 'Y')
				left = Math.max(left, x);
				else
					right = Math.min(right, x-1);
			}
			if (s.equals(">")){
				if (A == 'Y')
					left = Math.max(left, x+1);
				else
					right = Math.min(right, x);
			}
			
			if (s.equals("<=")){
				if ( A != 'Y')
				left = Math.max(left, x+1);
				else
					right = Math.min(right, x);
			}
			if (s.equals("<")){
				if (A != 'Y')
					left = Math.max(left, x);
				else
					right = Math.min(right, x-1);
			}
		}
		if (right < left)
			write("Impossible");
		else
			write(left);
	
	}
	private static long nextLong() throws  IOException {
		return Long.parseLong(next());
	}
	private static void writeln(Object t) {
		out.println(t);
	}
	private static void write(Object t) {
		out.print(t);
	}
	private static int nextInt() throws  IOException {
		return Integer.parseInt(next());
	}
	private static String next() throws IOException {
		while (!st.hasMoreElements())
			st = new StringTokenizer(in.readLine());
		
		return st.nextToken();
	}
	private static void begin() {
		out = new PrintWriter(new OutputStreamWriter(System.out));
		st = new StringTokenizer("");
		in = new BufferedReader(new InputStreamReader(System.in));
	}

}