﻿ C# - Sorting Algorithm - Insertion Sort

# C# - Sorting Algorithm - Insertion Sort

We often using sorting algorithm to sort numbers and strings. Also we have many sorting algorithms. I have explained here on how insertion sort algorithm works. Look at the yellow color high lighting section on output to understand how algorithm works after each iteration.

The complete program and test run output are given below:

## Source Code

using System;

using System.Collections.Generic;

using System.Text;

namespace ConsoleApplication1

{

class Program

{

static int InsertionSort()

{

Console.Write("\nProgram for Ascending order of Numeric Values using INSERTION SORT");

Console.Write("\n\nEnter the total number of elements: ");

int [] numarray = new int[max];

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

{

Console.Write("\nEnter [" + (i + 1).ToString() + "] element: ");

}

Console.Write("Before Sorting   : ");

for(int k = 0; k < max; k++)

Console.Write(numarray[k] + " ");

Console.Write("\n");

for(int i = 1; i < max; i++)

{

int j = i;

while(j > 0)

{

if(numarray[j-1] > numarray[j])

{

int temp = numarray[j - 1];

numarray[j - 1] = numarray[j];

numarray[j] = temp;

j--;

}

else

break;

}

Console.Write("After iteration " + i.ToString() + ": ");

for(int k = 0; k < max; k++)

Console.Write(numarray[k] + " ");

Console.Write("/*** " + (i + 1).ToString() + " numbers from the begining of the array are input and they are sorted ***/\n");

}

Console.Write("\n\nThe numbers in ascending orders are given below:\n\n");

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

{

Console.Write("Sorted [" + (i + 1).ToString() + "] element: ");

Console.Write(numarray[i]);

Console.Write("\n");

}

return 0;

}

static void Main(string[] args)

{

InsertionSort();

}

}

}

## Output

Program for Ascending order of Numeric Values using INSERTION SORT

Enter the total number of elements: 8

Enter [1] element: 80

Enter [2] element: 60

Enter [3] element: 40

Enter [4] element: 20

Enter [5] element: 10

Enter [6] element: 30

Enter [7] element: 50

Enter [8] element: 70

Before Sorting   : 80 60 40 20 10 30 50 70

After iteration 1: 60 80 40 20 10 30 50 70

After iteration 2: 40 60 80 20 10 30 50 70

After iteration 3: 20 40 60 80 10 30 50 70

After iteration 4: 10 20 40 60 80 30 50 70

After iteration 5: 10 20 30 40 60 80 50 70

After iteration 6: 10 20 30 40 50 60 80 70

After iteration 7: 10 20 30 40 50 60 70 80

The numbers in ascending orders are given below:

Sorted [1] element: 10

Sorted [2] element: 20

Sorted [3] element: 30

Sorted [4] element: 40

Sorted [5] element: 50

Sorted [6] element: 60

Sorted [7] element: 70

Sorted [8] element: 80