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 JAVA):

Solution:
function f(v){
  var r = "";
  if(v==">=")
    r = "<";
  else if (v=="<=")
    r = ">";
  else if (v=="<")
    r = ">=";
  else if (v==">")
    r = "<=";
  return r;
}
var min_ = -2000000000;
var max_ = 2000000000;
var n = readline();
var sign;
var num;
var yn;
for(var i = 0; i < n; i++)//error poner var
{
  var l = readline().split(' ');
  sign = l[0];
  num = +l[1];
  yn = l[2];
  if(yn=="N")
    sign = f(sign);//equivoque de variablr

  if(sign==">=")
    min_ = Math.max(num,min_);//libreria
  else if (sign=="<=")
    max_ = Math.min(num,max_);
  else if (sign=="<")
    max_ = Math.min(num - 1,max_);
  else if (sign==">")
    min_ = Math.max(num + 1,min_ );
}
if(min_ <= max_)   
  print(min_);
else
  print("Impossible");