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.lang.*;
import java.io.*;

//           THIS TEMPLATE MADE BY AKSH BANSAL.

public class Solution {
    static class FastReader {
        BufferedReader br;
        StringTokenizer st;

        public FastReader() {
            br = new BufferedReader(new InputStreamReader(System.in));
        }

        String next() {
            while (st == null || !st.hasMoreElements()) {
                try {
                    st = new StringTokenizer(br.readLine());
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return st.nextToken();
        }

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

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

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

        String nextLine() {
            String str = "";
            try {
                str = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            return str;
        }
    }

    public static void main(String[] args) throws IOException {
        FastReader sc = new FastReader();
        PrintWriter out = new PrintWriter(System.out);
        // ________________________________

//        int t = sc.nextInt();
//        StringBuilder output = new StringBuilder();
//
//        while (t-- > 0) {
//
//            output.append(solver()).append("\n");
//        }
//
//        out.println(output);
        // _______________________________

        int n = sc.nextInt();
        int min = (int)-2e9;
        int max = (int)2e9;
        int i=0;
        for(;i<n;i++){
            String[] s = sc.nextLine().split(" ");
            int num = Integer.valueOf(s[1]);
            boolean check = s[2].equals("Y")?true:false;
            // System.out.println("__"+ s[0]+ "_"+s[1]);
            if(s[0].equals(">=")){                    
                if(check){
                    if(max<num){
                        out.println("Impossible");
                        i = n+1;
                    }                    
                    min = Math.max(min, num);
                }
                else {
                    // <
                    if(min>=num){
                        out.println("Impossible");
                        i = n+1;
                    }                    
                    max = Math.min(max, num-1);
                }
            }
            else if(s[0].equals(">")){

                if(check){
                    if(max<=num){
                        out.println("Impossible");
                        i = n+1;
                    }                    
                    min = Math.max(min, num+1);
                }
                else {
                    // <=
                    if(min>num){
                        out.println("Impossible");
                        i = n+1;
                    }                    
                    max = Math.min(max, num);
                }
            }
            else if(s[0].equals("<=")){
                if(check){
                    if(min>num){
                        out.println("Impossible");
                        i = n+1;
                    }                    
                    max = Math.min(max, num);
                }
                else {
                    // <=
                    if(max<=num){
                        out.println("Impossible");
                        i = n+1;
                    }                    
                    min = Math.max(min, num+1);
                }

            }
            else {                    
                // System.out.println("__"+ "<");
                if(check){

                    if(min>=num){
                        out.println("Impossible");
                        i = n+1;
                    }                    
                    max = Math.min(max, num-1);
                }else {

                    if(max<num){
                        out.println("Impossible");
                        i = n+1;
                    }                    
                    min = Math.max(min, num);
                }
            }
            // System.out.println(min+"__"+ max);

        }
        if(i==n)out.println(min);
        // ________________________________
        out.flush();
    }

    public static int solver() {
        int res = 0;
        return res;
    }
}