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


public class r241_a {
	static StringTokenizer st;
	static BufferedReader br;
	static PrintWriter pw;
public static void main(String[] args)throws IOException {
	br=new BufferedReader(new InputStreamReader(System.in));
	pw=new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out))); 
	
	int n=nextInt(),z1=-(int)2e9,z2=(int)2e9,min=z2,max=z1;
	for (int i = 1; i <=n; i++) {
		String d=next();int x=nextInt();String y=next();
		if(d.equals("<")){
			if(y.equals("Y"))
			z2=x-1;
			else
				z1=x;
			min=Math.min(min, z2);
			max=Math.max(max, z1);
		}
		if(d.equals(">")){
			if(y.equals("Y"))
			z1=x+1;
			else
				z2=x;
			min=Math.min(min, z2);
			max=Math.max(max, z1);
		}
		if(d.equals("<=")){
			if(y.equals("Y"))
			z2=x;
			else
				z1=x+1;
			min=Math.min(min, z2);
			max=Math.max(max, z1);
		}
		if(d.equals(">=")){
			if(y.equals("Y"))
			z1=x;
			else
				z2=x-1;
			min=Math.min(min, z2);
			max=Math.max(max, z1);
		}
	}
	if(max<=min)
		pw.print(max);
	else
		pw.print("Impossible");
	pw.close();
	}
private static int nextInt()throws IOException{
	return Integer.parseInt(next());
}
private static long nextLong()throws IOException{
	return Long.parseLong(next());
}
private static double nextDouble()throws IOException{
	return Double.parseDouble(next());
}
private static String next()throws IOException {
	while (st==null||!st.hasMoreTokens())
	 st=new StringTokenizer(br.readLine());
	return st.nextToken();
}
}