CountOfEqualBitPairs

import java.util.Scanner;


public class _08_CountOfEqualBitPairs {

    public static void main(String[] args) {

        Scanner inputNum = new Scanner(System.in);
        long number = inputNum.nextLong();
        String binary = Long.toBinaryString(number);
        long binRep = Long.parseLong(binary);
        long binSubtr = binRep;
        long count = 0;

        for (int i = 0; i < binary.length(); i++) {
            long left = binSubtr;
            left = binSubtr%100;
            binSubtr/=10;
            if (left==11||left==0) {
                count++;
            }
        }
        System.out.println(count);
    }

}