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())
y = [-2*10**9,2*10**9]
k=[]
f=0
for i in range(n):
	k.append(list(map(str,input().split())))

for i in range(n):
	x = int(k[i][1])
	if k[i][2]=='N':
		if k[i][0]=='>':
			k[i][0]='<='
		elif k[i][0]=='>=':
			k[i][0]='<'
		elif k[i][0]=='<':
			k[i][0]='>='
		else:
			k[i][0]='>'
	if k[i][0]=='>':
		y[0]=max(x+1,y[0])
	elif k[i][0]=='<':
		y[1]=min(x-1,y[1])
	elif k[i][0]=='<=':
		y[1]=min(x,y[1])
	else:
		y[0]=max(x,y[0])
	if y[0]>y[1]:
		f=1
		break

if f :
	print("Impossible")
else:
	print(y[0])