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:
n = int(input())

a = []
for i in range(n):
	a.append(raw_input())

lower_bound = -2000000000
higher_bound = 2000000000

for i in a:
	string = i.split()
	number = int(string[1])
	if string[0] == '>':
		if string[2] == 'Y':
			lower_bound = max(lower_bound,number+1)
		else:
			higher_bound = min(higher_bound,number)
	elif string[0] == '<':
		if string[2] == 'Y':
			higher_bound = min(higher_bound,number-1)
		else:
			lower_bound = max(lower_bound,number)
	elif string[0] == '>=':
		if string[2] == 'Y':
			lower_bound = max(lower_bound,number)
		else:
			higher_bound = min(higher_bound,number-1)
	elif string[0] == '<=':
		if string[2] == 'Y':
			higher_bound = min(higher_bound,number)
		else:
			lower_bound = max(lower_bound,number+1)

	if lower_bound > higher_bound:
		print 'Impossible'
		exit(0)
if lower_bound <= 2000000000:
	print lower_bound
	exit(0)
if higher_bound >= -2000000000:
	print higher_bound
	exit(0)
print 'Impossible'