import java.util.Scanner;

public class Journals {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        
        String line = scanner.nextLine();
        
        int plus = 0;
        int minus = 0;

        char prev = 'a';
        for (int i = 0; i < line.length(); i++) {
            char curr = line.charAt(i);

            if (curr == prev) {
                if (curr == '+') {
                    plus++;
                } else {
                    minus++;
                }
            }

            prev = curr;
        }

        if (plus >= minus) {
            System.out.println(plus);
        } else {
            System.out.println(minus);
        }
    }
}