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())
low=-2000000000
upper=2000000000
f=0
while(n>0):
	s=raw_input().split()
	if(s[0]=='>='):
		if(s[2]=='Y'):
			if(upper<int(s[1])):
				print "Impossible"
				f=1
				break
			if(low<int(s[1])):
				low=int(s[1])
		else:
			if(low>=int(s[1])):
				print "Impossible"
				f=1
				break
			else:
				if(upper>int(s[1])):
					upper=int(s[1])
	elif(s[0]=='>'):
		if(s[2]=='Y'):
			if(upper <= int(s[1])):
				print "Impossible"
				f=1
				break
			if(low<=int(s[1])):
				low=int(s[1])+1
		else:
			if(low>int(s[1])):
				print "Impossible"
				f=1
				break
			else:
				if(upper>=int(s[1])):
					upper=int(s[1])
	elif(s[0]=='<='):
		if(s[2]=='Y'):
			if(low > int(s[1])):
				print "Impossible"
				f=1
				break
			if(upper>int(s[1])):
				upper=int(s[1])
		else:
			if(upper <=int(s[1])):
				print "Impossible"
				f=1
				break
			else:
				if(low<int(s[1])):
					low=int(s[1])
	else:
		if(s[2]=='Y'):
#			print s[1],low
			if(low>=int(s[1])):
				print "Impossible"
				f=1
				break
			if(upper>=int(s[1])):
				upper=int(s[1])-1
		else:
			if(upper<int(s[1])):
				print "Impossible"
				f=1
				break
			else:
				if(low<int(s[1])):
					low=int(s[1])
	n-=1
#print low,upper
if(f==0):
	print (low+upper)/2

		
	n-=1