Category Archives: C#

C#. Assert. Defensive programming

Posted on 28.09.2017 by Stanislav_Panteleev

SO First of all Assert() method is available for Trace and Debug classes. Debug.Assert() is executing only in Debug mode. Trace.Assert() is executing in Debug and Release mode. Here is an example:

int i = 1 + 3;
        // Debug.Assert method in Debug mode fails, since i == 4
        Debug.Assert(i == 3);
        Debug.WriteLine(i == 3, "i is equal to 3");

        // Trace.Assert method in Release mode is not failing.
        Trace.Assert(i == 4);
        Trace.WriteLine(i == 4, "i is equla to 4");

        Console.WriteLine("Press a key to continue...");
        Console.ReadLine();

int i = 1 + 3;

// Debug.Assert method in Debug mode fails, since i == 4

Debug.Assert(i == 3);

Debug.WriteLine(i == 3, "i is equal to 3");

// Trace.Assert method in Release mode is not failing.

Trace.Assert(i == 4);

Trace.WriteLine(i == 4, "i is equla to 4");

Console.WriteLine("Press a key to continue...");

Console.ReadLine();

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C#. Symbol Table with Binary Search

Posted on 28.09.2017 by Stanislav_Panteleev

Basic here is 2 arrays keys and vals. Following methods are implemented contains size izEmpty get put delete iterator (IEnumerable) and others… Example illustrates some kind of dictionary with Key and Value, 2 examples – one just shows some standart … Continue reading →

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C#.Algo. Symbol Table Structrure on Linked list

Posted on 28.09.2017 by Stanislav_Panteleev

Jasewick origin Git Basic here is one linked list. Following methods are implemented first contains size izEmpty get put delete iterator (IEnumerable) Example illustrates some kind of dictionary with Key and Value, 2 examples – one just shows some standart … Continue reading →

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C#. PriorityQueue

Posted on 27.09.2017 by Stanislav_Panteleev

Git

   class PriorityQueue
    {
        private int[] pq; // inside array pyramid binary tree
        private int N = 0; // pq[0] not used

        public void Display()
        {
            foreach (int val in pq) Console.Write(val+" ");
        }

        public PriorityQueue(int maxN)
        {
            pq = new int[maxN + 1];
        }

        public bool isEmpty()
        {
            return N == 0;
        }

        public int size()
        {
            return N;
        }

        public void Enqueue(int el)
        {
            pq[++N] = el;
            swimUp(N);
        }

        public int Dequeue()
        {
            int max = pq[1];
            Swap(1, N--);
            //pq[N + 1] = null;
            swimDown(1);
            return max;
        }

        private void Swap(int i,int j)
        {            
            int temp = pq[i];
            pq[i] = pq[j];
            pq[j] = temp;
        }

        private void swimUp(int k)
        {
            while ((k > 1) && (pq[k / 2] < pq[k]))
            {                
                Swap(k/2,k);                
                k = k / 2;
            }
        }

        private void swimDown(int k)
        {
            while (2 * k <= N)
            {
                int j = 2 * k;
                if ((j < N) && (j < j + 1)) j++;
                if (!(k < j)) break;
                //swap
                Swap(k,j);               
                k = j;
            }
        }
    }

class PriorityQueue

{

private int[] pq; // inside array pyramid binary tree

private int N = 0; // pq[0] not used

public void Display()

{

foreach (int val in pq) Console.Write(val+" ");

}

public PriorityQueue(int maxN)

{

pq = new int[maxN + 1];

}

public bool isEmpty()

{

return N == 0;

}

public int size()

{

return N;

}

public void Enqueue(int el)

{

pq[++N] = el;

swimUp(N);

}

public int Dequeue()

{

int max = pq[1];

Swap(1, N--);

//pq[N + 1] = null;

swimDown(1);

return max;

}

private void Swap(int i,int j)

{

int temp = pq[i];

pq[i] = pq[j];

pq[j] = temp;

}

private void swimUp(int k)

{

while ((k > 1) && (pq[k / 2] < pq[k]))

{

Swap(k/2,k);

k = k / 2;

}

private void swimDown(int k)

{

while (2 * k <= N)

{

int j = 2 * k;

if ((j < N) && (j < j + 1)) j++;

if (!(k < j)) break;

//swap

Swap(k,j);

k = j;

}

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C#. PyramidSort

Posted on 27.09.2017 by Stanislav_Panteleev

Git

     class PyramidSort2
    {
         Int32 add2pyramid(Int32[] a, Int32 i, Int32 N)
        {
            Int32 imax;
            Int32 temp;
            if ((2 * i + 2) < N)
            {
                if (a[2 * i + 1] < a[2 * i + 2]) imax = 2 * i + 2;
                else imax = 2 * i + 1;
            }
            else imax = 2 * i + 1;

            if (imax >= N) return i;

            if (a[i] < a[imax])
            {
                temp = a[i];
                a[i] = a[imax];
                a[imax] = temp;

                if (imax < N / 2) i = imax;
            }
            return i;
        }


        public void Pyramid_Sort(Int32[] arr, Int32 len)
        {
            //step 1: building the pyramid
            for (Int32 i = len / 2 - 1; i >= 0; --i)
            {
                long prev_i = i;
                i = add2pyramid(arr, i, len);
                if (prev_i != i) ++i;
            }

            //step 2: sorting
            Int32 buf;
            for (Int32 k = len - 1; k > 0; --k)
            {
                buf = arr[0];
                arr[0] = arr[k];
                arr[k] = buf;
                Int32 i = 0, prev_i = -1;
                while (i != prev_i)
                {
                    prev_i = i;
                    i = add2pyramid(arr, i, k);
                }
            }
        }

    }

class PyramidSort2

{

Int32 add2pyramid(Int32[] a, Int32 i, Int32 N)

{

Int32 imax;

Int32 temp;

if ((2 * i + 2) < N)

{

if (a[2 * i + 1] < a[2 * i + 2]) imax = 2 * i + 2;

else imax = 2 * i + 1;

}

else imax = 2 * i + 1;

if (imax >= N) return i;

if (a[i] < a[imax])

{

temp = a[i];

a[i] = a[imax];

a[imax] = temp;

if (imax < N / 2) i = imax;

}

return i;

}

public void Pyramid_Sort(Int32[] arr, Int32 len)

{

//step 1: building the pyramid

for (Int32 i = len / 2 - 1; i >= 0; --i)

{

long prev_i = i;

i = add2pyramid(arr, i, len);

if (prev_i != i) ++i;

}

//step 2: sorting

Int32 buf;

for (Int32 k = len - 1; k > 0; --k)

{

buf = arr[0];

arr[0] = arr[k];

arr[k] = buf;

Int32 i = 0, prev_i = -1;

while (i != prev_i)

{

prev_i = i;

i = add2pyramid(arr, i, k);

}

Example of use

     PyramidSort2 ps = new PyramidSort2();

            Int32[] arr = new Int32[100];
            //заполняем массив случайными числами
            Random rd = new Random();
            for (Int32 i = 0; i < arr.Length; ++i)
            {
                arr[i] = rd.Next(1, 101);
            }
            System.Console.WriteLine("The array before sorting:");
            foreach (Int32 x in arr)
            {
                System.Console.Write(x + " ");
            }
            //сортировка
            ps.Pyramid_Sort(arr, arr.Length);

            System.Console.WriteLine("\n\nThe array after sorting:");
            foreach (Int32 x in arr)
            {
                System.Console.Write(x + " ");
            }
            System.Console.WriteLine("\n\nPress the <Enter> key");
            System.Console.ReadLine();
            //foreach (var val in a) Console.Write(val);

            Console.ReadLine();

PyramidSort2 ps = new PyramidSort2();

Int32[] arr = new Int32[100];

//заполняем массив случайными числами

Random rd = new Random();

for (Int32 i = 0; i < arr.Length; ++i)

{

arr[i] = rd.Next(1, 101);

}

System.Console.WriteLine("The array before sorting:");

foreach (Int32 x in arr)

{

System.Console.Write(x + " ");

}

//сортировка

ps.Pyramid_Sort(arr, arr.Length);

System.Console.WriteLine("\n\nThe array after sorting:");

foreach (Int32 x in arr)

{

System.Console.Write(x + " ");

}

System.Console.WriteLine("\n\nPress the <Enter> key");

System.Console.ReadLine();

//foreach (var val in a) Console.Write(val);

Console.ReadLine();

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C#. QuickSort – Hoar, Lomuto and Unknown Author

Posted on 27.09.2017 by Stanislav_Panteleev

Быстрая сортировка по Сейджвику

class QuickSort
    {
        public int Partition(ref int[] a, int lo, int hi)
        {        
            int i = lo;
            int j = hi + 1;
            int v = a[lo]; // central element
            while (true)
            {
                while (a[++i] < v) if (i == hi) break;
                while (v <= a[--j] ) if (j == lo) break;
                if (i >= j) break;
                Exch(ref a, i, j);
            }
            Exch(ref a, lo, j);
            return j;
        }

        public void Sort(ref int[] a, int lo, int hi)
        {
            if (hi <= lo) return;
            int j = Partition(ref a, lo, hi);
            Sort(ref a, lo, j-1);
            Sort(ref a, j+1, hi);
        }

        public void Exch(ref int[] a,int i,int j)
        {
            int temp = a[j];
            a[j] = a[i];
            a[i] = temp;
        }

        public void Test()
        {
            int[] a = new int[5] { 3, 1, 2, 0, 1 };
            Sort(ref a, 0, a.Length - 1);
            foreach (int i in a) Console.Write(i + " ");
        }
    }

class QuickSort

{

public int Partition(ref int[] a, int lo, int hi)

{

int i = lo;

int j = hi + 1;

int v = a[lo]; // central element

while (true)

{

while (a[++i] < v) if (i == hi) break;

while (v <= a[--j] ) if (j == lo) break;

if (i >= j) break;

Exch(ref a, i, j);

}

Exch(ref a, lo, j);

return j;

}

public void Sort(ref int[] a, int lo, int hi)

{

if (hi <= lo) return;

int j = Partition(ref a, lo, hi);

Sort(ref a, lo, j-1);

Sort(ref a, j+1, hi);

}

public void Exch(ref int[] a,int i,int j)

{

int temp = a[j];

a[j] = a[i];

a[i] = temp;

}

public void Test()

{

int[] a = new int[5] { 3, 1, 2, 0, 1 };

Sort(ref a, 0, a.Length - 1);

foreach (int i in a) Console.Write(i + " ");

}

Git Hoar realization (What is Hoar?)

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace QuickSortExample
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] a = { 3, 2, 5, 6 };
            QuickSortHoar qsh = new QuickSortHoar();
            qsh.Execute(ref a,0,a.Length-1);

            foreach (var val in a) Console.Write(val+" ");
            Console.Read();
        }
    }

    class QuickSortHoar
    {
        void Swap(ref int i,ref int j)
        {
            int temp = i;
            i = j;
            j = temp;
        }

         public void Execute(ref int[] a, int lo, int hi)
        {
            int p = a[(hi - lo) / 2 + lo];            
            int i = lo, j = hi;
            while (i <= j)
            {
                while (a[i] < p && i <= hi) ++i;
                while (a[j] > p && j >= lo) --j;
                if (i <= j)
                {              
                    Swap(ref a[i],ref a[j]);
                    ++i; --j;
                }
            }
            if (j > lo) Execute(ref a, lo, j);
            if (i < hi) Execute(ref a, i, hi);
        }
    }
}

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace QuickSortExample

{

class Program

{

static void Main(string[] args)

{

int[] a = { 3, 2, 5, 6 };

QuickSortHoar qsh = new QuickSortHoar();

qsh.Execute(ref a,0,a.Length-1);

foreach (var val in a) Console.Write(val+" ");

Console.Read();

}

class QuickSortHoar

{

void Swap(ref int i,ref int j)

{

int temp = i;

i = j;

j = temp;

}

public void Execute(ref int[] a, int lo, int hi)

{

int p = a[(hi - lo) / 2 + lo];

int i = lo, j = hi;

while (i <= j)

{

while (a[i] < p && i <= hi) ++i;

while (a[j] > p && j >= lo) --j;

if (i <= j)

{

Swap(ref a[i],ref a[j]);

++i; --j;

}

if (j > lo) Execute(ref a, lo, j);

if (i < hi) Execute(ref a, i, hi);

}

Lomuto realization

 class QuickSort2
    {

        void Swap(ref int i,ref int j)
        {
            int temp = i;
            i = j;
            j = temp;
        }

        // разделение массива по ключу key так, что левая часть - x <=key, правая часть - x > key
        private int Partition(int[] a, int lo, int hi)
        {            
            int key = a[hi];
            int i = lo - 1;
            for (int j = lo; j < hi; j++)
            {
                if (a[j] <= key) Swap(ref a[++i], ref a[j]);
            }
            Swap(ref a[++i], ref a[hi]);
            return i;          
        }


        // сортировка
        public void Execute(int[] a, int lo, int hi)
        {
            if (lo < hi)
            {
                int key = Partition(a, lo, hi);
                Execute(a, lo, key - 1);
                Execute(a, key + 1, hi);
            }
        }
    }

class QuickSort2

{

void Swap(ref int i,ref int j)

{

int temp = i;

i = j;

j = temp;

}

// разделение массива по ключу key так, что левая часть - x <=key, правая часть - x > key

private int Partition(int[] a, int lo, int hi)

{

int key = a[hi];

int i = lo - 1;

for (int j = lo; j < hi; j++)

{

if (a[j] <= key) Swap(ref a[++i], ref a[j]);

}

Swap(ref a[++i], ref a[hi]);

return i;

}

// сортировка

public void Execute(int[] a, int lo, int hi)

{

if (lo < hi)

{

int key = Partition(a, lo, hi);

Execute(a, lo, key - 1);

Execute(a, key + 1, hi);

}

Git SomeNewRealization

static void QuickSort(int[] a, int lo, int hi) // Works! https://gist.github.com/lbsong/6833729
        {
            if (lo >= hi)
            {
                return;
            }

            int num = a[lo];

            /*
            Console.WriteLine("Before");
            Console.WriteLine("pivot index = "+lo);
            Console.WriteLine("pivot value = " + a[lo]);            
            foreach (int val in a) Console.Write(val+" ");
            Console.WriteLine(" ");
            */

            int i = lo, j = hi;

            while (i < j)
            {
                while (i < j && a[j] >= num)
                {
                    j--;
                }

                a[i] = a[j];

                while (i < j && a[i] <= num)
                {
                    i++;
                }

                a[j] = a[i];
            }                             
            a[i] = num;
            /*
            Console.WriteLine("After");
            Console.WriteLine("pivot index = " + lo);
            Console.WriteLine("pivot value = " + a[lo]);
            Console.WriteLine("i index = " + i);
            Console.WriteLine("j index = " + j);
            foreach (int val in a) Console.Write(val + " ");
            Console.WriteLine(" ");
            */

            QuickSort(a, lo, i - 1);
            QuickSort(a, i + 1, hi);
        }

static void QuickSort(int[] a, int lo, int hi) // Works! https://gist.github.com/lbsong/6833729

{

if (lo >= hi)

{

return;

}

int num = a[lo];

Console.WriteLine("Before");

Console.WriteLine("pivot index = "+lo);

Console.WriteLine("pivot value = " + a[lo]);

foreach (int val in a) Console.Write(val+" ");

Console.WriteLine(" ");

int i = lo, j = hi;

while (i < j)

{

while (i < j && a[j] >= num)

{

j--;

}

a[i] = a[j];

while (i < j && a[i] <= num)

{

i++;

}

a[j] = a[i];

}

a[i] = num;

Console.WriteLine("After");

Console.WriteLine("pivot index = " + lo);

Console.WriteLine("pivot value = " + a[lo]);

Console.WriteLine("i index = " + i);

Console.WriteLine("j index = " + j);

foreach (int val in a) Console.Write(val + " ");

Console.WriteLine(" ");

QuickSort(a, lo, i - 1);

QuickSort(a, i + 1, hi);

}

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C#. Queue on linked list

Posted on 26.09.2017 by Stanislav_Panteleev

Git

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace QueueOnOneLinkedList
{
    class Program
    {
        static void Main(string[] args)
        {
            // fill stack with Count elements
            int Count = 10;
            CustomQueueOnLinkedList<string> queue = new CustomQueueOnLinkedList<string>();            
            Random r = new Random();
            Console.WriteLine("lets fill queue with Count elements");
            for (int i = 0; i < Count; i++)
            {
                int someRandomNumber = r.Next(100);
                queue.Enque(someRandomNumber.ToString());
            }

            
            // iterator
            foreach (var s in queue) { Console.WriteLine(s.ToString()); }
            
            Console.WriteLine("What size of queue now?");
            Console.WriteLine(queue.size());

            Console.WriteLine("lets take last 5 elements from queue");
            for (int i = 0; i < 5; i++)
            {
                Console.WriteLine(queue.Deque());
            }
            Console.WriteLine("What size of queue now?");
            Console.WriteLine(queue.size());
            Console.WriteLine("If queue isEmpty?");
            if (queue.isEmpty()) Console.WriteLine("Yes"); else Console.WriteLine("No");
            
            Console.ReadLine();

        }
    }

    class CustomQueueOnLinkedList<T> : IEnumerable<T>
    {

        Node<T> first;
        Node<T> last;
        private int N;

        class Node<T>
        {
            public T item;
            public Node<T> next;
        }

        public bool isEmpty()
        {
            return ((last == null) || (N == 0));
        }
        public int size()
        {
            return N;
        }

        public void Enque(T item)
        {
            Node<T> lastOld = last;
            last = new Node<T>();
            last.item = item;
            last.next = null;
            if (isEmpty()) first = last;else lastOld.next = last;
            N++;
        }

        public T Deque()
        {
            T item = first.item;
            first = first.next;
            if (isEmpty()) last = null;
            N--;
            return item;
        }

        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }

        public IEnumerator<T> GetEnumerator()
        {
            var node = first;
            while (node != null)
            {
                yield return node.item;
                node = node.next;
            }
        }

    }
}

100

101

102

103

104

using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace QueueOnOneLinkedList

{

class Program

{

static void Main(string[] args)

{

// fill stack with Count elements

int Count = 10;

CustomQueueOnLinkedList<string> queue = new CustomQueueOnLinkedList<string>();

Random r = new Random();

Console.WriteLine("lets fill queue with Count elements");

for (int i = 0; i < Count; i++)

{

int someRandomNumber = r.Next(100);

queue.Enque(someRandomNumber.ToString());

}

// iterator

foreach (var s in queue) { Console.WriteLine(s.ToString()); }

Console.WriteLine("What size of queue now?");

Console.WriteLine(queue.size());

Console.WriteLine("lets take last 5 elements from queue");

for (int i = 0; i < 5; i++)

{

Console.WriteLine(queue.Deque());

}

Console.WriteLine("What size of queue now?");

Console.WriteLine(queue.size());

Console.WriteLine("If queue isEmpty?");

if (queue.isEmpty()) Console.WriteLine("Yes"); else Console.WriteLine("No");

Console.ReadLine();

}

class CustomQueueOnLinkedList<T> : IEnumerable<T>

{

Node<T> first;

Node<T> last;

private int N;

class Node<T>

{

public T item;

public Node<T> next;

}

public bool isEmpty()

{

return ((last == null) || (N == 0));

}

public int size()

{

return N;

}

public void Enque(T item)

{

Node<T> lastOld = last;

last = new Node<T>();

last.item = item;

last.next = null;

if (isEmpty()) first = last;else lastOld.next = last;

N++;

}

public T Deque()

{

T item = first.item;

first = first.next;

if (isEmpty()) last = null;

N--;

return item;

}

System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()

{

return GetEnumerator();

}

public IEnumerator<T> GetEnumerator()

{

var node = first;

while (node != null)

{

yield return node.item;

node = node.next;

}

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C#.Algo.MergeSort

Posted on 26.09.2017 by Stanislav_Panteleev

Git

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MergeSort
{
    class Program
    {
        static void Main(string[] args)
        {
            int Count = 1000;
            Random r = new Random();
            int[] a = new int[Count];

            for (int i = 0; i < a.Length; i++)
            {
                a[i] = r.Next(100);
            }

            MergeSort ms = new MergeSort();
            ms.Execute(ref a);

            foreach (int i in a) Console.WriteLine(i);
            Console.ReadLine();
        }

        
    }

    public class MergeSort
    {

        private int[] aux;

        public void Execute(ref int[] a)
        {
            aux = new int[a.Length];
            Sort(a, 0, a.Length-1);
        }

        void Sort(int[] a,int lo,int hi)
        {
            if (hi <= lo) return;
            int mid = lo + (hi - lo) / 2;
           // Console.WriteLine("Sort a " + lo + " " + hi);
            Sort(a, lo, mid); 
            Sort(a, mid+1, hi);
            Merge(a,lo,mid,hi);
        }

        public void Merge(int[] a, int lo, int mid, int hi)
        {
            Console.WriteLine("Merge a " + lo + " "+mid+" " + hi);
            int i = lo, j = mid + 1;            
            for (int k = lo; k <= hi; k++) aux[k] = a[k];            
            for (int k = lo; k <= hi; k++)
            {
                if (i > mid) a[k] = aux[j++];  // left data is over, get data from right
                else if(j > hi) a[k] = aux[i++]; //right data is over, get data from left
                else if (aux[j] < aux[i]) a[k] = aux[j++]; // key from right  < key from left - get data from right
                else a[k] = aux[i++]; // key from right  >= key from left - get data from left
            }
        }

    }


}

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace MergeSort

{

class Program

{

static void Main(string[] args)

{

int Count = 1000;

Random r = new Random();

int[] a = new int[Count];

for (int i = 0; i < a.Length; i++)

{

a[i] = r.Next(100);

}

MergeSort ms = new MergeSort();

ms.Execute(ref a);

foreach (int i in a) Console.WriteLine(i);

Console.ReadLine();

}

public class MergeSort

{

private int[] aux;

public void Execute(ref int[] a)

{

aux = new int[a.Length];

Sort(a, 0, a.Length-1);

}

void Sort(int[] a,int lo,int hi)

{

if (hi <= lo) return;

int mid = lo + (hi - lo) / 2;

// Console.WriteLine("Sort a " + lo + " " + hi);

Sort(a, lo, mid);

Sort(a, mid+1, hi);

Merge(a,lo,mid,hi);

}

public void Merge(int[] a, int lo, int mid, int hi)

{

Console.WriteLine("Merge a " + lo + " "+mid+" " + hi);

int i = lo, j = mid + 1;

for (int k = lo; k <= hi; k++) aux[k] = a[k];

for (int k = lo; k <= hi; k++)

{

if (i > mid) a[k] = aux[j++]; // left data is over, get data from right

else if(j > hi) a[k] = aux[i++]; //right data is over, get data from left

else if (aux[j] < aux[i]) a[k] = aux[j++]; // key from right < key from left - get data from right

else a[k] = aux[i++]; // key from right >= key from left - get data from left

}

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C#. SelectionSort | InsertionSort | BubbleSort.shellSort

Posted on 26.09.2017 by Stanislav_Panteleev

Git

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SortExamplesSelectionSort
{
    class Program
    {
        static void Main(string[] args)
        {
            int Count = 10;
            Random r = new Random();
            int[] a = new int[Count];
            
            for (int i = 0; i < a.Length; i++)
            {
                a[i] = r.Next(1000);
            }

            //SelectionSort(ref a);
            //InsertionSort(ref a);
            //BubbleSort(ref a);
            shellSort2(ref a);

            foreach (int i in a) Console.WriteLine(i);
            Console.ReadLine();
            
        }

        static void SelectionSort(ref int[] a) // complexity O(n^2)
        {
            for (int i = 0; i < a.Length; i++)
            {
                int min = i;
                // find min
                for (int j = i; j < a.Length; j++)
                {
                    if (a[j] < a[min]) min = j;
                }

                // exchange
                int temp = a[i];
                a[i] = a[min];
                a[min] = temp;
            }
        }

        static void InsertionSort(ref int[] a) // complexity O(n^2)
        {
            for (int i = 0; i < a.Length; i++)
            {
                
                for (int j = i; j>0; j--)
                {
                    if (a[j] < a[j - 1])
                    {
                        // exchange
                        int temp = a[j];
                        a[j] = a[j-1];
                        a[j-1] = temp;
                    }
                }               
            }
        }

       

        static void shellSort2(ref int[] a)
        {
            int j;
            int step = a.Length / 2;
            while (step > 0)
            {
                for (int i = 0; i < (a.Length - step); i++)
                {
                    j = i;
                    while ((j >= 0) && (a[j] > a[j + step]))
                    {
                        int tmp = a[j];
                        a[j] = a[j + step];
                        a[j + step] = tmp;
                        j -= step;
                    }
                }
                step = step / 2;
            }
        }
    }
}

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace SortExamplesSelectionSort

{

class Program

{

static void Main(string[] args)

{

int Count = 10;

Random r = new Random();

int[] a = new int[Count];

for (int i = 0; i < a.Length; i++)

{

a[i] = r.Next(1000);

}

//SelectionSort(ref a);

//InsertionSort(ref a);

//BubbleSort(ref a);

shellSort2(ref a);

foreach (int i in a) Console.WriteLine(i);

Console.ReadLine();

}

static void SelectionSort(ref int[] a) // complexity O(n^2)

{

for (int i = 0; i < a.Length; i++)

{

int min = i;

// find min

for (int j = i; j < a.Length; j++)

{

if (a[j] < a[min]) min = j;

}

// exchange

int temp = a[i];

a[i] = a[min];

a[min] = temp;

}

static void InsertionSort(ref int[] a) // complexity O(n^2)

{

for (int i = 0; i < a.Length; i++)

{

for (int j = i; j>0; j--)

{

if (a[j] < a[j - 1])

{

// exchange

int temp = a[j];

a[j] = a[j-1];

a[j-1] = temp;

}

static void shellSort2(ref int[] a)

{

int j;

int step = a.Length / 2;

while (step > 0)

{

for (int i = 0; i < (a.Length - step); i++)

{

j = i;

while ((j >= 0) && (a[j] > a[j + step]))

{

int tmp = a[j];

a[j] = a[j + step];

a[j + step] = tmp;

j -= step;

}

step = step / 2;

}

Сортировка пузырьком

 static void BubbleSort(ref int[] a) // complexity O(n^2)
        {
       
            for (int i = 0; i < a.Length; i++)
            {

                for (int j = 0; j < a.Length-1; j++)
                {
                    if (a[j] > a[j+1])
                    {
                        // exchange
                        int temp = a[j+1];
                        a[j+1] = a[j];
                        a[j] = temp;
                    }
                }
            }           
        }

static void BubbleSort(ref int[] a) // complexity O(n^2)

{

for (int i = 0; i < a.Length; i++)

{

for (int j = 0; j < a.Length-1; j++)

{

if (a[j] > a[j+1])

{

// exchange

int temp = a[j+1];

a[j+1] = a[j];

a[j] = temp;

}

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C#. BagOnLinkedList

Posted on 22.09.2017 by Stanislav_Panteleev

Git

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace BagOnLinkedList
{
    class Program
    {
        static void Main(string[] args)
        {
            // fill stack with Count elements
            int Count = 10;
            Bag<string> bag = new Bag<string>();
            //FixedGenericsStack<string> stack = new FixedGenericsStack<string>(Count);
            Random r = new Random();
            Console.WriteLine("lets fill bag with Count elements");
            for (int i = 0; i < Count; i++)
            {
                int someRandomNumber = r.Next(100);
                bag.push(someRandomNumber.ToString());
            }

            // iterator
            foreach (var s in bag) { Console.WriteLine(s.ToString()); }

            Console.WriteLine("What size of bag now?");
            Console.WriteLine(bag.size());
       
            Console.WriteLine("If bag isEmpty?");
            if (bag.isEmpty()) Console.WriteLine("Yes"); else Console.WriteLine("No");

            Console.ReadLine();
        }
    }

    public class Bag<T>:IEnumerable<T>
    {
       
        Node<T> first;
        private int N;
        class Node<T>
        {
            public T item;
            public Node<T> next;
        }

        public bool isEmpty() { return (first == null) || (N == 0); }
        public int size() { return N; }
        public void push(T item)
        {
            // adding to the begining
            Node<T> oldfirst = first;
            first = new Node<T>();
            first.item = item;
            first.next = oldfirst;
            N++;
        }

        /* // no pop in stack method
        public T pop()
        {
            T item = first.item;
            first = first.next;
            N--;
            return item;
        }
        */
     
        System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }

        public IEnumerator<T> GetEnumerator()
        {
            var node = first;
            while (node != null)
            {
                yield return node.item;
                node = node.next;
            }
        }

    }


}

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

namespace BagOnLinkedList

{

class Program

{

static void Main(string[] args)

{

// fill stack with Count elements

int Count = 10;

Bag<string> bag = new Bag<string>();

//FixedGenericsStack<string> stack = new FixedGenericsStack<string>(Count);

Random r = new Random();

Console.WriteLine("lets fill bag with Count elements");

for (int i = 0; i < Count; i++)

{

int someRandomNumber = r.Next(100);

bag.push(someRandomNumber.ToString());

}

// iterator

foreach (var s in bag) { Console.WriteLine(s.ToString()); }

Console.WriteLine("What size of bag now?");

Console.WriteLine(bag.size());

Console.WriteLine("If bag isEmpty?");

if (bag.isEmpty()) Console.WriteLine("Yes"); else Console.WriteLine("No");

Console.ReadLine();

}

public class Bag<T>:IEnumerable<T>

{

Node<T> first;

private int N;

class Node<T>

{

public T item;

public Node<T> next;

}

public bool isEmpty() { return (first == null) || (N == 0); }

public int size() { return N; }

public void push(T item)

{

// adding to the begining

Node<T> oldfirst = first;

first = new Node<T>();

first.item = item;

first.next = oldfirst;

N++;

}

/* // no pop in stack method

public T pop()

{

T item = first.item;

first = first.next;

N--;

return item;

}

System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()

{

return GetEnumerator();

}

public IEnumerator<T> GetEnumerator()

{

var node = first;

while (node != null)

{

yield return node.item;

node = node.next;

}

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Category Archives: C#

C#. Assert. Defensive programming

C#. Symbol Table with Binary Search

C#.Algo. Symbol Table Structrure on Linked list

C#. PriorityQueue

C#. PyramidSort

C#. QuickSort – Hoar, Lomuto and Unknown Author

C#. Queue on linked list

C#.Algo.MergeSort

C#. SelectionSort | InsertionSort | BubbleSort.shellSort

C#. BagOnLinkedList

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