human
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
assistant
#Here is Python program to find any integer value of y that meets the criteria of all answers.

"""
Codeforces Round 241 Div 1 Problem A

Author  : chaotic_iak
Language: Python 3.3.4
"""

class InputHandlerObject(object):
    inputs = []

    def getInput(self, n = 0):
        res = ""
        inputs = self.inputs
        if not inputs: inputs.extend(input().split(" "))
        if n == 0:
            res = inputs[:]
            inputs[:] = []
        while n > len(inputs):
            inputs.extend(input().split(" "))
        if n > 0:
            res = inputs[:n]
            inputs[:n] = []
        return res
InputHandler = InputHandlerObject()
g = InputHandler.getInput

############################## SOLUTION ##############################
n = int(input().strip())
mn = -2*10**9
mx = 2*10**9
repl = [(">", "<="), (">=", "<"), ("<=", ">"), ("<", ">=")]
for i in range(n):
    a = g()
    a[1] = int(a[1])
    if a[2] == "N":
        for qq,qqq in repl:
            if qq == a[0]:
                a[0] = qqq
                break
    if a[0] == ">": a[1] += 1
    if a[0] == "<": a[1] -= 1
    if a[0][0] == ">": mn = max(mn, a[1])
    if a[0][0] == "<": mx = min(mx, a[1])

if mn <= mx:
    print(mn)
else:
    print("Impossible")