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.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedList;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Scanner;
import java.util.Stack;
import java.util.concurrent.PriorityBlockingQueue;

import javax.swing.ComboBoxEditor;

public class aa {

	public static void main(String[] args) throws IOException {

		BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
		PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out));
		StringBuilder q = new StringBuilder();
		int n = Integer.parseInt(in.readLine());
		int lower = Integer.MIN_VALUE;
		int upper = Integer.MAX_VALUE;
		for (int i = 0; i < n; i++) {
			String y[] = in.readLine().trim().split(" ");
			if (y[0].equals(">")) {
				if (y[2].equals("Y")) {
					lower = Math.max(lower, Integer.parseInt(y[1]) + 1);
				} else {
					upper = Math.min(upper, Integer.parseInt(y[1]));
				}
			} else if (y[0].equals(">=")) {
				if (y[2].equals("Y")) {
					lower = Math.max(lower, Integer.parseInt(y[1]));
				} else {
					upper = Math.min(upper, Integer.parseInt(y[1]) - 1);
				}
			} else if (y[0].equals("<")) {
				if (y[2].equals("Y")) {
					upper = Math.min(upper, Integer.parseInt(y[1]) - 1);
				} else {
					lower = Math.max(lower, Integer.parseInt(y[1]));
				}
			} else if (y[0].equals("<=")) {
				if (y[2].equals("Y")) {
					upper = Math.min(upper, Integer.parseInt(y[1]));
				} else {
					lower = Math.max(lower, Integer.parseInt(y[1]) + 1);
				}
			}
		}

		if (lower > upper)
			q.append("Impossible\n");
		else {
			if (lower != Integer.MIN_VALUE)
				q.append(lower + "\n");
			else
				q.append(upper + "\n");

		}
		out.print(q);
		out.close();

	}
}