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.util.*;
import java.io.*;
import java.math.BigInteger;


public class Backyard {	

static Scanner sc = new Scanner(System.in);
static InputStreamReader stream = new InputStreamReader(System.in);
static BufferedReader br = new BufferedReader(stream);

	public static void main(String[] args) throws IOException{
		int n = Integer.parseInt(br.readLine());
		int ul=2000000000,ll=-2000000000;
		for(int i=0 ; i<n ; i++) {
			String[] arr = br.readLine().split(" ");
			if(arr[0].equals(">")) {
				if(arr[2].equals("Y")) {
					ll=Math.max(ll,Integer.parseInt(arr[1])+1);
				}else {
					ul=Math.min(ul,Integer.parseInt(arr[1]));
				}
			}else if(arr[0].equals("<")) {
				if(arr[2].equals("Y")) {
					ul=Math.min(ul,Integer.parseInt(arr[1])-1);
				}else {
					ll=Math.max(ll,Integer.parseInt(arr[1]));
				}
			}else if(arr[0].equals(">=")) {
				if(arr[2].equals("Y")) {
					ll=Math.max(ll,Integer.parseInt(arr[1]));
				}else {
					ul=Math.min(ul,Integer.parseInt(arr[1])-1);
				}
			}else {
				if(arr[2].equals("Y")) {
					ul=Math.min(ul,Integer.parseInt(arr[1]));
				}else {
					ll=Math.max(ll,Integer.parseInt(arr[1])+1);
				}
			}
		}
		if(ll>ul)System.out.println("Impossible");
		else System.out.println(ll);
	}
	public static int[] readArrayline(int n) throws IOException{
		int[] a = new int[n];
		String[] s = br.readLine().split(" ");
		for(int i=0 ; i<n ; i++) {
			a[i]= Integer.parseInt(s[i]);
		}
		return a;
	}	

}