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.InputStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Deque;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Stack;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.util.StringTokenizer;
import java.util.TreeSet;
public class cfvc15
{
	static BufferedReader reader;
    static StringTokenizer tokenizer;
    static void init(InputStream input) 
    {
        reader = new BufferedReader( new InputStreamReader(input) );
        tokenizer = new StringTokenizer("");
    }
    static String next() throws IOException
    {
        while ( ! tokenizer.hasMoreTokens() )
        {
            tokenizer = new StringTokenizer(reader.readLine() );
        }
        return tokenizer.nextToken();
    }
 
    static long nextInt() throws IOException 
    {
        return Long.parseLong( next() );
    }
	static PrintWriter writer;
	static void outit(OutputStream outputStream)
	{
		writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
	}
	static void print(Object...objects) {
		for (int i = 0; i < objects.length; i++) 
		{
			if (i != 0)
				writer.print(' ');
			writer.print(objects[i]);
		}
	}
 
	static void println(Object...objects) {
		print(objects);
		writer.println();
	}
 
	static void close() {
		writer.close();
	}
 
	static void flush() {
		writer.flush();
	}
	public static void print_a(long [] a)
    {
    	for(long i : a)
    	{
    		print(i+" ") ;
    	}
    	println() ;
    }
    public static void main(String [] args) throws IOException
    {
    	init(System.in) ;
    	outit(System.out) ;
//    	int t = (int) nextInt() ;
//    	for(int i =0 ; i<t ; i++)
    	output() ;
        flush();
        close();
    }
    static long mod = 1000000007 ;
    static ArrayList<ArrayList<Integer>> ar ;
    static int [] c ;
    public static void output() throws IOException
    {
    	int n = (int) nextInt() ;
    	long l = (long) -Math.pow(10,11) ;
    	long h = (long)Math.pow(10,11) ;
    	for(int i = 0 ; i<n ; i++)
    	{
    		int t = 0 ;
    		String s1 = next() ;
    		long val = nextInt() ;
    		String s2 = next() ;
    		if(s1.equals(">"))
    		{
    			if(s2.equals("Y"))
    			{
    				t = 1 ;
    			}
    			else
    			{
    				t = 4 ;
    			}
    		}
    		else if(s1.equals("<"))
    		{
    			if(s2.equals("Y"))
    			{
    				t = 2 ;
    			}
    			else
    			{
    				t = 3 ;
    			}
    		}
    		else if(s1.equals(">="))
    		{
    			if(s2.equals("Y"))
    			{
    				t = 3 ;
    			}
    			else
    			{
    				t = 2 ;
    			}
    		}
    		else if(s1.equals("<="))
    		{
    			if(s2.equals("Y"))
    			{
    				t = 4 ;
    			}
    			else
    			{
    				t = 1 ;
    			}
    		}
    		if(t==1)
    		{
    			l = Math.max(val+1,l) ;
    		}
    		else if(t==2)
    		{
    			h = Math.min(val-1,h) ;
    		}
    		else if(t==3)
    		{
    			l = Math.max(val,l) ;
    		}
    		else if(t==4)
    		{
    			h = Math.min(val,h) ;
    		}
    	}
    	if(l<=h)
    	{
    		println((long)Math.max(-2*Math.pow(10,9),l)) ;
    	}
    	else
    	{
    		println("Impossible") ;
    	}
    }
}