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:
list1=["","","",""]
n=int(input())
for _ in range(n):
    list2=[x for x in input().split()]
    val=int(list2[1])
    if list2[2]=='N':

        if list2[0]=='>=':
            list2[0]='<'

        elif list2[0]=='>':
            list2[0]='<='

        elif list2[0]=='<=':
            list2[0]='>'

        elif list2[0]=='<':
            list2[0]='>='

    if list2[0]=='>=':
        if list1[1]=="":
            list1[0]='['
            list1[1]=val
        else:
            if list1[1]<=val:
                list1[1]=val
                list1[0]='['
    elif list2[0]=='>':
        if list1[1]=="":
            list1[0]='('
            list1[1]=val
        else:
            if list1[1]<=val:
                list1[1]=val
                list1[0]='('
    elif list2[0]=='<=':
        if list1[2]=="":
            list1[3]=']'
            list1[2]=val
        else:
            if list1[2]>=val:
                list1[2]=val
                list1[3]=']'
    elif list2[0]=='<':
        if list1[2]=="":
            list1[3]=')'
            list1[2]=val
        else:
            if list1[2]>=val:
                list1[2]=val
                list1[3]=')'

if list1[0]=='(':
    list1[1]+=1
if list1[3]==')':
    list1[2]-=1

if list1[0]=="" or list1[3]=="":
    if list1[0]=="":
        print(list1[2])
    else:
        print(list1[1])
else:
    if list1[1]>list1[2]:
        print('Impossible')
    else:
        print(list1[1])