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:
from random import randrange
n=int(raw_input())
l=[]
for i in range(n):
    x=raw_input().split()
    if x[2]=='N':
        if x[0]=='>':
            x[2]='Y'
            x[0]='<='
        elif x[0]=='<':
            x[2]='Y'
            x[0]='>='
        elif x[0]=='>=':
            x[2]='Y'
            x[0]='<'
        elif x[0]=='<=':
            x[2]='Y'
            x[0]='>'
    l.append(x)

ansg,ansge,ansl,ansle=-(10**9)-1,-(10**9)-1,(10**9)+1,(10**9)+1
ans=0
for i in range(0,len(l)):
    if l[i][0]=='>':
        ansg=max(ansg,int(l[i][1])+1)
    elif l[i][0]=='<':
        ansl=min(ansl,int(l[i][1])-1)
    elif l[i][0]=='>=':
        ansge=max(ansge,int(l[i][1]))
    elif l[i][0]=='<=':
        ansle=min(ansle,int(l[i][1]))

anslowerbound=max(ansg,ansge)
ansupperbound=min(ansl,ansle)
#print 'lower bound = ' + str(anslowerbound)
#print 'upper bound = ' + str(ansupperbound)
if anslowerbound>ansupperbound:
    print 'Impossible'
elif anslowerbound == ansupperbound:
    print anslowerbound
else:
    print randrange(anslowerbound,ansupperbound+1)