#2CountOfEqualBitPairs

import java.util.Scanner;

public class CountOfEqualBitPairs {
    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);
        int input = scan.nextInt();
        String binaryNum = Integer.toBinaryString(input);
        int counterOfPairs = 0;
        for (int i = 0; i < binaryNum.length() - 1; i++) {
            if (binaryNum.charAt(i) == binaryNum.charAt(i+1)) {
                counterOfPairs++;
            }
        }
        System.out.println(counterOfPairs);
    }
}