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>
#pragma comment(linker, "/STACK:20000000")
using namespace std;
int ri() {
  int x;
  scanf("%d", &x);
  return x;
}
long long rll() {
  long long x;
  scanf("%lld", &x);
  return x;
}
void solve() {
  int lx = -2e9, rx = 2e9;
  int n = ri();
  for (int i = (int)(1); i <= (int)(n); i++) {
    string s;
    cin >> s;
    int x = ri();
    string answer;
    cin >> answer;
    if (answer == "N") {
      if (s == ">=")
        s = "<";
      else if (s == "<=")
        s = ">";
      else if (s == "<")
        s = ">=";
      else if (s == ">")
        s = "<=";
    }
    int l, r;
    if (s == ">=") l = x, r = 2e9;
    if (s == "<=") l = -2e9, r = x;
    if (s == ">") l = x + 1, r = 2e9;
    if (s == "<") l = -2e9, r = x - 1;
    int mx = max(l, lx);
    int mn = min(r, rx);
    if (mx > mn) {
      cout << "Impossible" << endl;
      return;
    }
    lx = mx, rx = mn;
  }
  if (lx == 2e9) lx--;
  cout << lx << endl;
}
int main() {
  solve();
  return 0;
}