#include <bits/stdc++.h>

using namespace std;

int main(void) {
  string s;
  cin >> s;

  int w = 0;
  for (int i = 0; i < s.size(); i++) {
    if (s[i] == 'c') continue;
    w = i;
    break;
  }
  cout << min(w - 1, (int)s.size() - w) << endl;

  return 0;
}