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;
const int INF = 0x3f3f3f3f;
const long long INFL = 0x3f3f3f3f3f3f3f3f;
int read();
char gchar();
const int maxn = 10000 + 50;
char FALSE[20] = "Impossible";
int main() {
  int n;
  scanf("%d", &n);
  int lans = -2e9;
  int rans = 2e9;
  char a, b, c;
  int d;
  for (int i = 1; i <= n; ++i) {
    a = gchar();
    b = getchar();
    scanf("%d", &d);
    c = gchar();
    if (c == 'Y') {
      if (a == '>') {
        if (b == ' ')
          lans = max(lans, d + 1);
        else
          lans = max(d, lans);
      } else {
        if (b == ' ')
          rans = min(d - 1, rans);
        else
          rans = min(d, rans);
      }
    } else {
      if (a == '<') {
        if (b == ' ')
          lans = max(lans, d);
        else
          lans = max(lans, d + 1);
      } else {
        if (b == ' ')
          rans = min(rans, d);
        else
          rans = min(rans, d - 1);
      }
    }
    if (rans < lans) {
      printf("%s\n", FALSE);
      exit(0);
    }
  }
  printf("%d\n", lans);
  return 0;
}
int read() {
  int ret = 0, flag = 1;
  char c = getchar();
  while (c == ' ' || c == '\n') c = getchar();
  if (c == '-')
    flag = -1;
  else {
    ret = ret * 10;
    ret = ret + (c - '0');
  }
  c = getchar();
  while (c != ' ' && c != '\n' && '0' <= c && c <= '9') {
    ret = ret * 10;
    ret = ret + (c - '0');
    c = getchar();
  }
  return ret * flag;
}
char gchar() {
  char ret = getchar();
  while (ret == ' ' || ret == '\n') ret = getchar();
  return ret;
}