using System;

​

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Bit Count 9: " + BitCount(9));

​

        Console.WriteLine("Bit Count 43: " + BitCount(43));

        Console.WriteLine("Bit Count 243: " + BitCount(243));

        Console.WriteLine("Bit Count 1243: " + BitCount(1243));

        Console.WriteLine("Bit Range 42, 5, 2 :" + BitCountRange(42,2,5));

    }

    public static int BitCount(int num)

    {

        string s= "";

        int count = 0;

        int i =0;

        int bitval;

        do

        {

            bitval = 1 << i;

            //Console.WriteLine("bitval: " + bitval);

            if((num & bitval) == bitval)

            {

                count++;

                s = "1" + s;

            //Console.WriteLine(bitval);

            }

            else{

                s = "0" + s;

            }

            i++;

        }while(bitval <= num);

        Console.WriteLine(num + " :" + s);

​

        return count;

    }

    //l <= r >= 1

    public static int BitCountRange(int num, int l, int r)

    {

        int count = 0;

        int num2 = ((1 << r) - 1) ^ ((1 << (l - 1)) - 1); 

        Console.WriteLine("num2 " + num2);

        for(int i = l+1; i>=r-1; i--)

        {

            int bitval = 1 << i;

            if((num & bitval) == bitval)

            {

                count++;

                Console.WriteLine(bitval);

            }

        }

        return count;

    }

    /* Function to reverse bits of num 

    Time Complexity: O(n)

    Space Complexity: O(1)

    */

    public static int reverseBits(int num) 

    { 

        int NO_OF_BITS = sizeof(int) * 8; 

        int reverse_num = 0, i, temp; 

​

        for (i = 0; i < NO_OF_BITS; i++) 

        { 

            temp = (num & (1 << i)); 

            if(temp > 0) 

                reverse_num |= (1 << ((NO_OF_BITS - 1) - i)); 

        } 

​

        return reverse_num; 

    } 

​

/* Driver function to test above function */

​

​

}