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:
//package codeForcesTry;

import java.io.BufferedReader;
import java.io.Closeable;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.StringTokenizer;

public class A416_GuessNumber implements Closeable{
	BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
	PrintWriter writer = new PrintWriter(System.out);
	StringTokenizer stringTokenizer;

	String next() throws IOException {
	    while (stringTokenizer == null || !stringTokenizer.hasMoreTokens()) {
	        stringTokenizer = new StringTokenizer(reader.readLine());
	    }
	    return stringTokenizer.nextToken();
	}

	double nextDouble() throws IOException {
	    return Double.parseDouble(next());
	}

	int nextInt() throws IOException {
	    return Integer.parseInt(next());
	}

	long nextLong() throws IOException {
	    return Long.parseLong(next());
	}
	String comp[]={">","<",">=","<="};
	public void solve() throws IOException{
	int n=nextInt();
	String a[]=new String[n];
	int num[]=new int[n];
	String b[]=new String[n];
	int min=(int) (Math.pow(10,9)*2),max=(int) (-Math.pow(10,9)*2);

	
	for(int i=0;i<n;i++){
		String x=reader.readLine();
		String y[]=x.split(" ");
		a[i]=y[0];
		num[i]=Integer.parseInt(y[1]);
		b[i]=y[2];
		if (b[i].equals("N")) {
			if (a[i].equals(">")) a[i] = comp[3]; 
			else if (a[i].equals("<")) a[i] = comp[2]; 
			else if (a[i].equals(">=")) a[i] = comp[1]; 
			else if (a[i].equals("<=")) a[i] = comp[0];				
		}
		if(a[i].equals(comp[0])){
	
				max=Math.max(max,num[i]+1);
		
		}
		else if(a[i].equals(comp[1])){
		
				min=Math.min(min,num[i]-1);
		
		}
		else if(a[i].equals(comp[2])){
			max=Math.max(num[i],max);
		}
		else if(a[i].equals(comp[3])){
			
				min=Math.min(min,num[i]);
			
		}
		//System.out.println(min+" "+max+" "+num[i]+" "+a[i]);
	}
	if(min<max)
		writer.println("Impossible");
	else
		writer.println(max);
	
	}
	public static void main(String args[]) throws IOException{ 
		try(A416_GuessNumber c=new A416_GuessNumber()){
		c.solve();
		}
	}
	public void close() throws IOException {
	    reader.close();
	    writer.close();
	}

}