import java.util.*;
import java.math.*;

public class Main {
    private static Scanner sc = new Scanner(System.in);
    public static void main(String[] args) throws Exception {
        String s = sc.next();
        int ret = 10000;
        int cnt = 0;
        for (int i = 0;i < s.length();i++) {
            if (s.charAt(i)=='c') cnt++;
        }
        ret = Math.min(cnt-1,s.length()-cnt);
        System.out.println(ret);
    }
}