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.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) throws NumberFormatException, IOException {
		 BufferedReader br = new BufferedReader (new InputStreamReader(System.in));
	        PrintWriter pw = new PrintWriter(new BufferedOutputStream(System.out));
	        int a = Integer.parseInt(br.readLine());
	        long i1 = -2*1000000000;
	        long i2 = 2*1000000000;
	        int temp = 0;
	        for(int i = 0;i<a;i++){
	            String[] z = br.readLine().split(" ");
	            if(z[0].equals(">=")){
	                temp = Integer.parseInt(z[1]);
	                if(z[2].equals("Y")){
	                    if(temp>i1)
	                        i1 = temp;
	                }
	                else{
	                    if(temp<i2)
	                        i2 = temp;
	                }
	            }
	            if(z[0].equals(">")){
	                temp = Integer.parseInt(z[1]);
	                if(z[2].equals("Y")){
	                    if(temp+1>i1)
	                    i1 = temp+1;
	                }
	                else{
	                    if(temp<i2)
	                    i2 = temp;
	                }
	            }
	            if(z[0].equals("<=")){
	                temp = Integer.parseInt(z[1]);
	                if(z[2].equals("Y")){
	                    if(temp<i2)
	                    i2 = temp;
	                }
	                else{
	                    if(temp+1>i1)
	                    i1 = temp+1;
	                }
	            }
	            if(z[0].equals("<")){
	                temp = Integer.parseInt(z[1]);
	                if(z[2].equals("Y")){
	                    if(temp-1<i2)
	                    i2 = temp-1;
	                }
	                else{
	                    if(temp>i1)
	                    i1 = temp;
	                }
	            }
	        }
	        if(i1>i2){
	            pw.println("Impossible");
	        }
	        else{
	           pw.println(i1);
	        }
	        pw.close();
	}
	

}