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.Locale;
import java.util.Scanner;

public class GuessNumberSolver {

    private int n;
    private Question[] questions;

    private int high = (int) (2 * 1E9);
    private int low = -high;

    public static void main(String[] args) {
        GuessNumberSolver solver = new GuessNumberSolver();

        solver.readData();
        int solution = solver.solve();

        if (solution == Integer.MAX_VALUE) {
            solver.print("Impossible");
        } else {
            solver.print(solution);
        }
    }

    private int gcd(int a, int b) {
        return b == 0 ? a : gcd(b, a % b);
    }

    private int lcm(int a, int b) {
        return a * b / gcd(a, b);
    }

    private void print(int[] values) {
        StringBuilder builder = new StringBuilder();

        for (int value : values) {
            builder.append(value);
            builder.append(" ");
        }

        print(builder);
    }

    private void print(Object value) {
        System.out.println(value);
    }

    private void print(boolean value) {
        System.out.println(value ? "YES" : "NO");
    }

    private void print(int value) {
        System.out.println(value);
    }

    private void print(long value) {
        System.out.println(value);
    }

    private void print(double value) {
        System.out.printf(Locale.ENGLISH, "%.10f", value);
    }

    private int[] getDigits(int number) {
        int[] digits = new int[10];
        int index = digits.length - 1;
        int digitsCount = 0;

        while (number > 0) {
            digits[index] = number % 10;
            number /= 10;
            index--;
            digitsCount++;
        }

        int[] result = new int[digitsCount];

        System.arraycopy(digits, digits.length - digitsCount, result, 0, digitsCount);

        return result;
    }

    private int[] readArray(Scanner scanner, int size) {
        int[] result = new int[size];

        for (int i = 0; i < size; i++) {
            result[i] = scanner.nextInt();
        }

        return result;
    }

    private void readData() {
        Scanner scanner = new Scanner(System.in);

        int n = scanner.nextInt();
        questions = new Question[n];
        for (int i = 0; i < n; i++) {
            questions[i] = new Question();
            questions[i].sign = scanner.next();
            questions[i].x = scanner.nextInt();
            questions[i].answer = scanner.next();
        }
    }

    private int solve() {
        for (Question q : questions) {
            if (q.sign.equals("<")) {
                if (q.answer.equals("Y")) {
                    high = Math.min(high, q.x - 1);
                } else {
                    low = Math.max(low, q.x);
                }
            } else if (q.sign.equals(">")) {
                if (q.answer.equals("Y")) {
                    low = Math.max(low, q.x + 1);
                } else {
                    high = Math.min(high, q.x);
                }
            } else if (q.sign.equals("<=")) {
                if (q.answer.equals("Y")) {
                    high = Math.min(high, q.x);
                } else {
                    low = Math.max(low, q.x + 1);
                }
            } else {
                if (q.answer.equals("Y")) {
                    low = Math.max(low, q.x);
                } else {
                    high = Math.min(high, q.x - 1);
                }
            }
        }

        return low <= high ? low : Integer.MAX_VALUE;
    }

    private static class Question {
        private String sign;
        private int x;
        private String answer;
    }
}