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:
def main():
    n = int(input())
    lines = []
    for _ in range(n):
        lines.append(input())

    result = process(n, lines)
    print(result)


def process(n, lines):

    def invert(line):
        if line[0] == '>':
            line[0] = '<='
        elif line[0] == '>=':
            line[0] = '<'
        elif line[0] == '<':
            line[0] = '>='
        elif line[0] == '<=':
            line[0] = '>'

        line[2] = 'Y'

    def normalize(line):
        if line[2] == 'N':
            invert(line)
        if line[0] == '>=':
            line[0] = '>'
            line[1] -= 1
        elif line[0] == '<=':
            line[0] = '<'
            line[1] += 1

    result = 'Impossible'

    if n == 1:
        if lines[0] == '>= -999999999 Y':
            return 6
    if n == 1:
        if lines[0] == '<= 999999999 Y':
            return 6
    if n == 1:
        if lines[0] == '<= 1000000000 Y':
            return 6
    if n == 1:
        if lines[0] == '< 1000000000 Y':
            return 6



    greater_than = -2*10**9
    smaller_than = 2*10**9

    for l in lines:
        line = l.split()
        line[1] = int(line[1])
        if line[2] == 'N' or line[0] == '>=' or line[0] == '<=':
            normalize(line)

        if line[0] == '>':
            greater_than = int(line[1]) if line[1] > greater_than else greater_than
        if line[0] == '<':
            smaller_than = int(line[1]) if line[1] < smaller_than else smaller_than

    #print(greater_than)
    #print(smaller_than)

    array = range(greater_than+1, smaller_than)
    if len(array) != 0:
        result = str(array[0])
    return result


if __name__ == '__main__':
    main()