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 CPP):

Solution:
#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, c, l, r, flag, m;
  char a[5], b[5];
  while (scanf("%d", &n) != EOF) {
    l = -2000000000;
    r = 2000000000;
    flag = 1;
    while (n--) {
      memset(a, 0, sizeof(a));
      memset(b, 0, sizeof(b));
      scanf("%s", a);
      scanf("%d", &c);
      scanf("%s", b);
      if (!flag) continue;
      int s = strlen(a);
      if (b[0] == 'Y')
        m = 1;
      else
        m = 0;
      if ((s == 2 && a[0] == '>') || (s == 1 && a[0] == '<')) {
        if ((s == 1 && m) || (s == 2 && !m)) {
          if (l >= c)
            flag = 0;
          else
            r = min(r, c - 1);
        } else {
          if (r < c)
            flag = 0;
          else
            l = max(l, c);
        }
      }
      if ((s == 2 && a[0] == '<') || (s == 1 && a[0] == '>')) {
        if ((s == 1 && m) || (s == 2 && !m)) {
          if (r < c)
            flag = 0;
          else
            l = max(l, c + 1);
        } else {
          if (l > c)
            flag = 0;
          else
            r = min(r, c);
        }
      }
    }
    if (!flag)
      printf("Impossible\n");
    else
      printf("%d\n", l);
  }
  return 0;
}