#include <iostream>
#include <string>
using namespace std;
int main() {
    string input;
    cin >> input;

    int left = 0, right = 0;

    char previous = input[0];
    char last = input[input.size() - 1];

    int len = input.size();

    for( int i = 1; i < len; i++ ) {
        if( input[i] == previous ) {
            if(previous == '-') {
                left ++;
            }
            if(previous == '+') {
                right ++;
            }
        }

        previous = input[i];
    }

    if( last == '-' ) left ++;
    else right ++;

    int out = min(left, right);

    cout << out << endl;

    return 0;
}