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.util.Scanner;
import java.util.*;
public class Main
{
static class FastReader
{
BufferedReader br;
StringTokenizer st;
public FastReader()
{
br = new BufferedReader(new
InputStreamReader(System.in));
}
String next()
{
while (st == null || !st.hasMoreElements())
{
try
{
st = new StringTokenizer(br.readLine());
}
catch (IOException e)
{
e.printStackTrace();
}
}
return st.nextToken();
}
int nextInt()
{
return Integer.parseInt(next());
}
long nextLong()
{
return Long.parseLong(next());
}
double nextDouble()
{
return Double.parseDouble(next());
}
String nextLine()
{
String str = "";
try
{
str = br.readLine();
}
catch (IOException e)
{
e.printStackTrace();
}
return str;
}
}


public static void main(String[] args)
{
FastReader fs=new FastReader();
int n = fs.nextInt();

long lessthan = 2 * 1000 * 1000 * 1000;  // mx
long greaterthan = -1*lessthan;   // mn


while(n-- > 0)
{
    String[] s = fs.nextLine().split(" ");
    long num = Long.parseLong(s[1]);
    String s1 = new String("");
    
    
    
    
    
    if( s[0].compareTo("<=")==0 )
    {
        if(s[2].compareTo("Y")==0)
        {
            lessthan = Math.min( lessthan, num );
        }
        else
        {
            greaterthan = Math.max(greaterthan,num+1 );
        }
    }
    else if(s[0].compareTo(">=")==0)
    {
        if(s[2].compareTo("N")==0)
        {
            lessthan = Math.min(lessthan, num-1 );
        }
        else
        {
            greaterthan = Math.max(greaterthan,num);
        }
    }
    else if(s[0].compareTo("<")==0)
    {
        if(s[2].compareTo("Y")==0)
        {
            lessthan = Math.min(lessthan, num-1 );
        }
        else
        {
            greaterthan = Math.max(greaterthan,num);
        }
    }
    else
    {
        if(s[2].compareTo("N")==0)
        {
            lessthan = Math.min( lessthan, num );
        }
        else
        {
            greaterthan = Math.max(greaterthan,num+1 );
        }
    }
}

if( lessthan < greaterthan )
{
    System.out.println("Impossible");
}
else
{
    System.out.println(greaterthan);
}

}
}