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())
left = None
right = None
for i in range(n):
    st = input()
    op, num, ans = st.split(' ')
    num = int(num)
    if ans == 'N':
        if op == '>=':
            op = '<'
        elif op == '>':
            op = '<='
        elif op == '<=':
            op = '>'
        else:
            op = '>='
    if op == '>=':
        if left == None:
            left = num
        else:
            left = max(left, num)
    elif op == '>':
        if left == None:
            left = num+1
        else:
            left = max(left, num+1)
    elif op == '<=':
        if right == None:
            right = num
        else:
            right = min(right, num)
    else: # op == '<'
        if right == None:
            right = num-1
        else:
            right = min(right, num-1)
if left == None and right == None:
    print(0)
elif left == None:
    print(right)
elif right == None:
    print(left)
elif left > right:
    print('Impossible')
else:
    print(left)