#include <bits/stdc++.h>   using namespace std;   bool check(string s) {     string t = s;     reverse(t.begin(), t.end());     return (s == t);   }   int main() {     string s;     cin >> s;     int l = 0, r = ((int)s.length()) - 1;     set<char> all;     while (l < r) {       all.insert(s[l]);       all.insert(s[r]);       l++;       r--;     }     if (all.size() <= 1) {       cout <<  Impossible  << endl;       return 0;     }     for (int i = 0; i < ((int)s.length()) - 1; i++) {       string fi =   , se =   ;       for (int j = 0; j <= i; j++) fi += s[j];       for (int j = i + 1; j < (int)s.length(); j++) se += s[j];       if (check(se + fi) && (se + fi != s)) {         cout << 1 << endl;         return 0;       }     }     cout << 2 << endl;     return 0;   }   