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.*;

public class MainA {
	class FastIO {
		BufferedReader br;
		StringTokenizer st;
		PrintWriter out;

		public FastIO(File in, File o) {
			try {
				br = new BufferedReader(new FileReader(in));
				out = new PrintWriter(new FileWriter(o));
			} catch (Exception e) {
				e.printStackTrace();
			}
			eat("");
		}

		public FastIO() {
			br = new BufferedReader(new InputStreamReader(System.in));
			out = new PrintWriter(new OutputStreamWriter(System.out));
			eat("");
		}

		public void eat(String s) {
			st = new StringTokenizer(s);
		}

		public String nextLine() {
			try {
				return br.readLine();
			} catch (IOException e) {
				throw new IOError(e);
			}
		}

		public boolean hasNext() {
			while (!st.hasMoreTokens()) {
				String s = nextLine();
				if (s == null)
					return false;
				eat(s);
			}
			return true;
		}

		public String next() {
			hasNext();
			return st.nextToken();
		}

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

		public long nextLong() {
			return Long.parseLong(next());
		}

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

		public void print(String ans) {
			out.print(ans);
			out.flush();
		}

		public void print(int ans) {
			out.print(ans);
			out.flush();
		}

		public void print(long ans) {
			out.print(ans);
			out.flush();
		}

		public void print(double ans) {
			out.print(ans);
			out.flush();
		}

		public void println(String ans) {
			out.println(ans);
			out.flush();
		}

		public void println(int ans) {
			out.println(ans);
			out.flush();
		}

		public void println(long ans) {
			out.println(ans);
			out.flush();
		}

		public void println(double ans) {
			out.println(ans);
			out.flush();
		}

		public void println() {
			println("");
			out.flush();
		}

		public void printf(String arg0, Object... arg1) {
			out.printf(arg0, arg1);
			out.flush();
		}

		public void println(int[] ans) {
			for (int i = 0; i < ans.length; i++)
				print(ans[i] + " ");
			println();
		}

		public void println(long[] ans) {
			for (int i = 0; i < ans.length; i++)
				print(ans[i] + " ");
			println();
		}

		public void println(double[] ans) {
			for (int i = 0; i < ans.length; i++)
				print(ans[i] + " ");
			println();
		}

		public void println(Object... ans) {
			for (Object cur : ans)
				print(cur.toString() + " ");
			println();
		}

		public void println(Object ans[][]) {
			for (int i = 0; i < ans.length; i++) {
				for (int j = 0; j < ans[i].length; i++) {
					print(ans[i] + " ");
				}
				println();
			}
		}

		public void println(int ans[][]) {
			for (int i = 0; i < ans.length; i++) {
				for (int j = 0; j < ans[i].length; i++) {
					print(ans[i] + " ");
				}
				println();
			}
		}

		public void println(long ans[][]) {
			for (int i = 0; i < ans.length; i++) {
				for (int j = 0; j < ans[i].length; i++) {
					print(ans[i] + " ");
				}
				println();
			}
		}

		public void println(double ans[][]) {
			for (int i = 0; i < ans.length; i++) {
				for (int j = 0; j < ans[i].length; i++) {
					print(ans[i] + " ");
				}
				println();
			}
		}

		public void println(List<Object> ans) {
			for (Object i : ans) {
				print(i.toString() + " ");
			}
			println();
		}

		public void close() {
			out.flush();
			out.close();
		}
	}

	// FastIO scan = new FastIO(new File("in"), new File("out"));

	FastIO scan = new FastIO();

	public void run() {

		int n = scan.nextInt();
		int max = 2000000000;
		int min = -2000000000;
		for (int i = 0; i < n; i++) {
			String a = scan.next();
			int b = scan.nextInt();
			String c = scan.next();
			if (a.equals("<")) {
				if (c.equals("Y")) {
					max = Math.min(max, b - 1);
				} else {
					min = Math.max(b, min);
				}
			} else if (a.equals("<=")) {
				if (c.equals("Y")) {
					max = Math.min(max, b);
				} else {
					min = Math.max(b + 1, min);
				}
			} else if (a.equals(">")) {
				if (c.equals("Y")) {
					min = Math.max(min, b + 1);
				} else {
					max = Math.min(b, max);
				}
			} else if (a.equals(">=")) {
				if (c.equals("Y")) {
					min = Math.max(min, b);
				} else {
					max = Math.min(b-1, max);
				}
			}
		}
		// scan.println(max,min);
		if(max > 2000000000 && min < -2000000000){
			scan.println("Impossible");
		}
		else if (max >= min)
			scan.println(min);
		else
			scan.println("Impossible");

		scan.close();
	}

	public static void main(String args[]) throws Exception {
		new MainA().run();
	}
}