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.*;
import java.math.*;
import java.util.*;

import org.omg.CORBA.Environment;

//Codeforces
public class MainCodeforces1 {
	private static MyScanner in;
	private static PrintStream out;
	private static boolean LOCAL_TEST = false;

	private static void solve() throws IOException
	{
		int ymin = Integer.MIN_VALUE;
		int ymax = Integer.MAX_VALUE;
		int n = in.nextInt();
		for (int i = 0; i < n; i++) {
			String eq = in.nextString();
			int x = in.nextInt();
			String yn = in.nextString();
			if (yn.equals("Y")) {
				if (eq.equals(">=")) {
					if (x > ymin)
						ymin = x;
				}
				else if (eq.equals("<")) {
					if (x - 1 < ymax)
						ymax = x - 1;
				}
				else if (eq.equals(">")) {
					if (x + 1 > ymin)
						ymin = x + 1;
				}
				else if (eq.equals("<=")) {
					if (x < ymax)
						ymax = x;
				}
			}
			else {
				if (eq.equals("<")) {
					if (x > ymin)
						ymin = x;
				}
				else if (eq.equals(">=")) {
					if (x - 1 < ymax)
						ymax = x - 1;
				}
				else if (eq.equals("<=")) {
					if (x + 1 > ymin)
						ymin = x + 1;
				}
				else if (eq.equals(">")) {
					if (x < ymax)
						ymax = x;
				}
			}
		}
		if (ymin <= ymax) {
			ymin = Math.max(ymin, -2000000000);
			ymin = Math.min(ymin, 2000000000);
			out.println(ymin);
		}
		else
			out.println("Impossible");

	}

	public static void main(String[] args) throws IOException {
		// helpers for input/output
		out = System.out;
		try {
			String cname = System.getenv("COMPUTERNAME");
			if (!cname.equals(""))
				LOCAL_TEST = true;
		} catch (Exception e) {
		}
		if (LOCAL_TEST) {
			in = new MyScanner("E:\\zin.txt");
		}
		else {
			boolean usingFileForIO = false;
			if (usingFileForIO) {
				// using input.txt and output.txt as I/O
				in = new MyScanner("input.txt");
				out = new PrintStream("output.txt");
			}
			else {
				in = new MyScanner();
				out = System.out;
			}
		}

		solve();
	}

	// =====================================
	static class MyScanner {
		BufferedReader bufReader;
		StringTokenizer strTok;

		public MyScanner() throws IOException
		{
			bufReader = new BufferedReader(new InputStreamReader(System.in));
			strTok = new StringTokenizer("");
		}

		public MyScanner(String inputFile) throws IOException {
			bufReader = new BufferedReader(new InputStreamReader(
					new FileInputStream(
							inputFile)));
			strTok = new StringTokenizer("");
		}

		String GetNextToken() throws IOException {
			if (!strTok.hasMoreTokens())
				strTok = new StringTokenizer(bufReader.readLine());
			return strTok.nextToken();
		}

		public int nextInt() throws IOException {
			return Integer.valueOf(GetNextToken());
		}

		public long nextLong() throws IOException {
			return Long.valueOf(GetNextToken());
		}

		public double nextDouble() throws IOException {
			return Double.valueOf(GetNextToken());
		}

		public String nextString() throws IOException {
			return GetNextToken();
		}

		public String nextLine() throws IOException {
			return bufReader.readLine();
		}

		public int countTokens() {
			return strTok.countTokens();
		}

		public boolean hasMoreTokens() {
			return strTok.hasMoreTokens();
		}
	}

}