Problem 8. * Count of Equal Bit Pairs

import java.util.Scanner;

public class _8_Problem {

    public static void main(String[] args) {

                Scanner input = new Scanner(System.in);

        int n = input.nextInt();
        int countBits = 0;

        while (n > 0){
                int last2Bits = (n >> 32) & 3; // 3 in binnary is 11
                if (last2Bits == 0 || last2Bits == 3)
                {
                    countBits++;
                }
                n = n >> 1;
            }
        System.out.println(countBits);
    }
}