#include <bits/stdc++.h>
using namespace std;
typedef long long ll;


int main() {
  string s;
  cin >> s;
  int n = s.size();
  int cnt = 0;
  for (int i = 0; i < n; ++i) {
    cnt += s[i] == 'c';
  }

  int wcnt = n - cnt;
  int ans = min(cnt - 1, wcnt);
  cout << ans << '\n';
  return 0;
}