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 PYTHON3):

Solution:
n = int(input())

operations = [">=", "<=", ">", "<"]
NO = "N"
M = 2*10**9
greater = []
less = []

for i in range(n):
	inp = input().split(" ")
	if inp[0] == operations[0] and inp[2] == NO:
		inp[0] = operations[3]
	elif inp[0] == operations[1] and inp[2] == NO:
		inp[0] = operations[2]
	elif inp[0] == operations[2] and inp[2] == NO:
		inp[0] = operations[1]
	elif inp[0] == operations[3] and inp[2] == NO:
		inp[0] = operations[0]

	if inp[0] == operations[0]:
		greater.append(int(inp[1]) - 1)
	elif inp[0] == operations[2]:
		greater.append(int(inp[1]))
	elif inp[0] == operations[1]:
		less.append(int(inp[1]) + 1)
	elif inp[0] == operations[3]:
		less.append(int(inp[1]))

upper = 0
if len(greater) == 0:
	upper = -1 * M
else:
	upper = greater[0]
	for i in range(1, len(greater)):
		if greater[i] > upper:
			upper = greater[i]

lower = 0
if len(less) == 0:
	lower = M
else:
	lower = less[0]
	for i in range(1, len(less)):
		if less[i] < lower:
			lower = less[i]


if upper < -1 * M:
	upper = -1 * M
if lower > M:
	lower = M

if upper > lower - 2:
	print("Impossible")

else:
	print(upper + 1)