#include <bits/stdc++.h>
using namespace std;
int main() {
  string s;
  cin >> s;
  int cnt[26] = {};
  for (long long(i) = 0; (i) < (long long)(s.size()); (i)++) cnt[s[i] - 'a'];
  int even = 0;
  vector<char> koho;
  for (long long(i) = 0; (i) < (long long)(26); (i)++) {
    if (cnt[i] % 2 == 1) {
      even++;
      koho.push_back((char)('a' + i));
    }
  }
  if (even <= 1) {
    cout << 1 << endl;
    return 0;
  }
  return 0;
}
