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:
left_border_inclusive = float("-inf")
right_border_inclusive = float("inf")

inverse_signs = {
    ">": "<=",
    "<=": ">",
    ">=": "<",
    "<": ">="
}

NUMBERS = int(input())
EXTRA_FINISH = False

sign, value = None, None
for _ in range(NUMBERS):
    sign, value, answer = input().split(' ')
    value = int(value)
    if answer == "N":
        sign = inverse_signs[sign]

    if sign == ">":
        if value >= right_border_inclusive:
            EXTRA_FINISH = True
            break
        left_border_inclusive = max(left_border_inclusive, value + 1)
    elif sign == ">=":
        if value > right_border_inclusive:
            EXTRA_FINISH = True
            break
        left_border_inclusive = max(left_border_inclusive, value)
    elif sign == "<":
        if value <= left_border_inclusive:
            EXTRA_FINISH = True
            break
        right_border_inclusive = min(right_border_inclusive, value-1)
    elif sign == "<=":
        if value < left_border_inclusive:
            EXTRA_FINISH = True
            break
        right_border_inclusive = min(right_border_inclusive, value)

if not EXTRA_FINISH:
    if left_border_inclusive == float("-inf"):
        print(right_border_inclusive)
    else:
        print(left_border_inclusive)
else:
    print("Impossible")