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 PYTHON):

Solution:
import sys
from sys import stdout
T = int(raw_input())
L = -2000000000
R = 2000000000
while T:
    op,N,answer = raw_input().split(" ")
    N = int(N)
    if op == ">=":
        op = "<"
        if answer == 'Y':
            answer = 'N'
        else:
            answer = 'Y'
    elif op == "<=":
        op = ">"
        if answer == 'Y':
            answer = 'N'
        else:
            answer = 'Y'
    if op == ">":
        if answer == 'Y':
            if N >= R:
                stdout.write("Impossible")
                sys.exit(0)
            else:
                L = max(L, N+1)
        else:
            if N < L:
                stdout.write("Impossible")
                sys.exit(0)
            else:
                R = min(R, N)
    elif op == "<":
        if answer == 'Y':
            if N <= L:
                stdout.write("Impossible")
                sys.exit(0)
            else:
                R = min(R, N-1)
        else:
            if N > R:
                stdout.write("Impossible")
                sys.exit(0)
            else:
                L = max(L, N)
    T = T-1

stdout.write(str(L))