using System;

public class Program

{

    public static void Main()

    {

​

        while (true)

        {

            Console.Write("Enter a number:  Range number : Min value = 0, Max value = ");

            Console.WriteLine(uint.MaxValue + " : \n");

​

            string line = Console.ReadLine();

​

            uint number;

​

            bool result = uint.TryParse(line, out number);

​

            if (result == false) //not an uint number

            {

                Console.WriteLine("\nThis is not a valid input for uint number!\n\n");

            }

            else//the input for number is valid

            {

                Console.WriteLine("\nEnter a value for position [p]:  Range p : Min value p = 0, Max value p = 31 ! \n");

​

                line = Console.ReadLine();

​

                int p;  // mask can take values from 1 to 1000 0000 0000 0000 0000 0000 0000 0000 for uint

                // type uint has 32 bits word, so k = 32

                // position p takes values from 0 to 31 

                // bits are numbered from 0 to 31 , from right to left

                result = int.TryParse(line, out p);

​

                if (result == false || p < 0 || p > 31)

                {

                    Console.WriteLine(result == false ? "\nThis is not a valid input for p!\n\n"

                                                      :

                                                        "\nOut of range!\n\n");

                }

                else //the input for p is valid

                {

                    Console.WriteLine("\nEnter a value for position [q]:  Range q : Min value q = 0, Max value q = 31 ! \n");

​

                    line = Console.ReadLine();

​

                    int q;

                    result = int.TryParse(line, out q);

​

                    if (result == false || q < 0 || q > 31)

                    {

                        Console.WriteLine(result == false ? "\nThis is not a valid input for q!\n\n"

                                                             :

                                                             "\nTOut of range!\n\n");

                    }

                    else//input for q is valid

                    {

                        int MaxValueOfK;

​

                        if (p > q)

                        {

                            MaxValueOfK = 32 - p;

                        }

                        else // q > p

                        {

                            MaxValueOfK = 32 - q;

                        }

                        Console.WriteLine("\nEnter a value for [k]!   Range k : Min value k = 0, Max value k = " + MaxValueOfK + " !\n");

​

                        line = Console.ReadLine();

​

                        int k;

                        result = int.TryParse(line, out k);

​

                        if (result == false || p + k > 32 || q + k > 32) //not a valid  integer number or k is out of it's range

                        {

                            Console.WriteLine(result == false ? "\nThis is not a valid input for k!\n\n"

                                                                :

                                                                "\nOut of range!\n\n");

                        }

                        else //input for k is valid

                        {

                            // condition for bits overlapping: 

​

                            bool overlap = (p < q && p + k >= q) || (q < p && q + k >= p);

​

                            //checks for bits overlapping :

                            if (overlap)

                            {

                                Console.WriteLine("\nOverlapping !\n\n");

                            }

                            else // no bits overlaps

                            {

                                // swap p with q, p+1 with q+1, p+2 with q+2, ....., p+k-1 with q+k-1

​

                                int bitPValue;

                                int bitQValue;

​

                                uint maskP;

                                uint maskQ;

​

                                for (int i = 0; i <= k - 1; i++)

                                {

                                    //geting the value from the bit in position [p] 

                                    maskP = 1u << p;

                                    bitPValue = (int)(number & maskP) >> p; // 0 or 1

​

                                    //geting the value from the bit in position [q]

                                    maskQ = 1u << q;

                                    bitQValue = (int)(number & maskQ) >> q; //O or 1

​

​

                                    //replacing the value in the q-bit with the value in the p-bit 

​

                                    if (bitPValue == 1) //so we are inserting value [1] in q

                                    {

                                        // change the q-Bit Value to 1

                                        number = number | maskQ;

                                    }

                                    else //bitPValue = 0, so we are insertin value [0] in q

                                    {

                                        // change the q-Bit Value to 0

                                        maskQ = ~maskQ;

                                        number = number & maskQ;

                                    }

​

                                    //replacing the value in the p-bit with the value in the q-bit 

​

                                    if (bitQValue == 1) //so, we are inserting value [1] in p

                                    {

                                        // changing the p-Bit Value to 1

                                        number = number | maskP;

                                    }

                                    else // bitQValue == 0, so we are inserting value [0] in p

                                    {

                                        // changing the p-Bit Value to 0

                                        maskP = ~maskP;

                                        number = number & maskP;

                                    }

                                    p++;

                                    q++;

                                }

                                Console.WriteLine("\nResult : \n\n" + number + " \n\n\n");

                            }

                        }

                    }

                }

            }

        }

    }

}

​

​