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;
signed main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long t;
  t = 1;
  while (t--) {
    long long n;
    cin >> n;
    string s;
    long long x;
    char y;
    vector<long long> v1{-1000000007}, v2{1000000007}, v3{-1000000007},
        v4{1000000007};
    for (long long i = 0; i < n; i++) {
      cin >> s >> x >> y;
      if (y == 'Y') {
        if ((long long)s.size() == 1) {
          if (s[0] == '>')
            v1.push_back(x);
          else
            v2.push_back(x);
        } else {
          if (s[0] == '>')
            v3.push_back(x);
          else
            v4.push_back(x);
        }
      } else {
        if ((long long)s.size() == 1) {
          if (s[0] == '>')
            v4.push_back(x);
          else
            v3.push_back(x);
        } else {
          if (s[0] == '>')
            v2.push_back(x);
          else
            v1.push_back(x);
        }
      }
    }
    if (max(*max_element(v1.begin(), v1.end()) + 1,
            *max_element(v3.begin(), v3.end())) != -1000000006)
      if (min(*min_element(v2.begin(), v2.end()) - 1,
              *min_element(v4.begin(), v4.end())) != 1000000006)
        if (max(*max_element(v1.begin(), v1.end()) + 1,
                *max_element(v3.begin(), v3.end())) <=
            min(*min_element(v2.begin(), v2.end()) - 1,
                *min_element(v4.begin(), v4.end())))
          cout << max(*max_element(v1.begin(), v1.end()) + 1,
                      *max_element(v3.begin(), v3.end()));
        else
          cout << "Impossible";
      else
        cout << max(*max_element(v1.begin(), v1.end()) + 1,
                    *max_element(v3.begin(), v3.end()));
    else
      cout << min(*min_element(v2.begin(), v2.end()) - 1,
                  *min_element(v4.begin(), v4.end()));
  }
}