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 trim(s) {
    return s.replace(/^\s+|\s+$/gm, '');
}

function tokenize(s) {
    return trim(s).split(/\s+/);
}
function main() {
    minValue=-2*1000*1000*1000;
    maxValue=2*1000*1000*1000;
    var n = trim(readline());
    for(var i=0; i<n; ++i) {
        var tokens=trim(readline()).split(/\s+/);
        var r=tokens[0];
        var x=parseInt(tokens[1]);
        var a=tokens[2];
        if("Y"==a) {
            if(">="==r) minValue=Math.max(minValue, x);
            if(">"==r) minValue=Math.max(minValue, x+1);
            if("<="==r) maxValue=Math.min(maxValue, x);
            if("<"==r) maxValue=Math.min(maxValue, x-1);
        } else {
            if("<"==r) minValue=Math.max(minValue, x);
            if("<="==r) minValue=Math.max(minValue, x+1);
            
            if(">"==r) maxValue=Math.min(maxValue, x);
            if(">="==r) maxValue=Math.min(maxValue, x-1);
        }
    }
    if(minValue<=maxValue) print(minValue);
    else print("Impossible");
}
main();