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.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.StringTokenizer;



public class A{
	
	
	public static void main(String[] args)throws Exception {
		Scanner sc = new Scanner(System.in);
		PrintWriter out = new PrintWriter(System.out);
		int q = sc.nextInt();
		long lo = -2*1000000000L , hi = 2* 1000000000L;
		while(q-->0)
		{
			String tmp = sc.next(); int x = sc.nextInt() ; char ans = sc.next().charAt(0);
			if(tmp.equals(">="))
			{
				if(ans == 'Y')
					if(x>hi)
						{System.out.println("NO");return;}
					else lo = Math.max(lo, x);
				else 
					if(x<=lo)
						{System.out.println("NO");return;}
					else hi = Math.min(hi, x-1);
			}
			else if(tmp.equals("<="))
			{
				if(ans == 'Y')
					if(x<lo)
						{System.out.println("Impossible");return;}
					else hi = Math.min(hi, x);
				else 
					if(x>=hi)
						{System.out.println("Impossible");return;}
					else lo = Math.max(lo, x+1);
			}
			else if(tmp.equals(">"))
			{
				if(ans == 'Y')
					if(x>=hi)
						{System.out.println("Impossible");return;}
					else lo = Math.max(lo, x+1);
				else 
					if(x<lo)
						{System.out.println("Impossible");return;}
					else hi = Math.min(hi, x);
			}
			else if(tmp.equals("<")) 
			{
				if(ans == 'Y')
					if(x<=lo)
						{System.out.println("Impossible");return;}
					else hi = Math.min(hi, x-1);
				else 
					if(x>hi)
						{System.out.println("Impossible");return;}
					else lo = Math.max(lo, x);
			}
		}
		out.print(lo);
		out.flush();
		out.close();
	}
	

	static class Scanner {
		StringTokenizer st;
		BufferedReader br;

		public Scanner(InputStream s) {
			br = new BufferedReader(new InputStreamReader(s));
		}

		public Scanner(FileReader r) {
			br = new BufferedReader(r);
		}

		public String next() throws IOException {
			while (st == null || !st.hasMoreTokens())
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}

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

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

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

		public double nextDouble() throws IOException {
			String x = next();
			StringBuilder sb = new StringBuilder("0");
			double res = 0, f = 1;
			boolean dec = false, neg = false;
			int start = 0;
			if (x.charAt(0) == '-') {
				neg = true;
				start++;
			}
			for (int i = start; i < x.length(); i++)
				if (x.charAt(i) == '.') {
					res = Long.parseLong(sb.toString());
					sb = new StringBuilder("0");
					dec = true;
				} else {
					sb.append(x.charAt(i));
					if (dec)
						f *= 10;
				}
			res += Long.parseLong(sb.toString()) / f;
			return res * (neg ? -1 : 1);
		}

		public boolean ready() throws IOException {
			return br.ready();
		}

	}

}