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C++ program to implement Insertion sort using class

Ranjith — Tue, 01 Feb 2011 13:27:51 +0000

#include 
const int MAX = 10 ;
class array
{
	private :
		int arr[MAX] ;
		int count ;
	public :
		array( ) ;
		void add ( int item ) ;
		void sort( ) ;
		void display( ) ;
} ;
array :: array( )
{
	count = 0 ;
	for ( int i = 0 ; i < MAX ; i++ )
		arr[i] = 0 ;
}
void array :: add ( int item )
{
	if ( count < MAX )
	{
		arr[count] = item ;
		count++ ;
	}
	else
		cout << "\nArray is full" << endl ;
}
void array :: sort( )
{
	int temp ;
	for ( int i = 1 ; i <= count - 1 ; i++ )
	{
		for ( int j = 0 ; j < i ; j++ )
		{
			if ( arr[j] > arr[i] )
			{
				temp = arr[j] ;
				arr[j] = arr[i] ;
				for ( int k = i ; k > j ; k-- )
					arr[k] = arr[k - 1] ;
				arr[k + 1] = temp ;
			}
		}
	}
}
 
void array :: display( )
{
	for ( int i = 0 ; i < count ; i++ )
		cout << arr[i] << "\t" ;
	cout << endl ;
}
void main( )
{
	array a ;
	a.add ( 25 ) ;
	a.add ( 17 ) ;
	a.add ( 31 ) ;
	a.add ( 13 ) ;
	a.add ( 2 ) ;
	cout << "\nInsertion sort.\n" ;
	cout << "\nArray before sorting:" << endl ;
	a.display( ) ;
	a.sort( ) ;
	cout << "\nArray after insertion sorting:" << endl ;
	a.display( ) ;
}

Insertion sort in C program

Ranjith — Thu, 04 Dec 2008 06:12:42 +0000

Here is the program to sort the given integer in ascending order using insertion sort method. Please find the pictorial tutor of the insertion sorting.

Logic : Here, sorting takes place by inserting a particular element at the appropriate position, that’s why the name- insertion sorting. In the First iteration, second element A[1] is compared with the first element A[0]. In the second iteration third element is compared with first and second element. In general, in every iteration an element is compared with all the elements before it. While comparing if it is found that the element can be inserted at a suitable position, then space is created for it by shifting the other elements one position up and inserts the desired element at the suitable position. This procedure is repeated for all the elements in the list.

If we complement the if condition in this program, it will give out the sorted array in descending order. Sorting can also be done in other methods, like selection sorting and bubble sorting, which follows in the next pages.

Insertion Sort Demo

C program for Insertion Sort:

#include
void main()
{
	int A[20], N, Temp, i, j;
	clrscr();
	printf("\n\n\t ENTER THE NUMBER OF TERMS...: ");
	scanf("%d", &N);
	printf("\n\t ENTER THE ELEMENTS OF THE ARRAY...:");
	for(i=0; i<N; i++)
	{
		gotoxy(25,11+i);
		scanf("\n\t\t%d", &A[i]);
	}
	for(i=1; i<N; i++)
	{
		Temp = A[i];
		j = i-1;
		while(Temp<A[j] && j>=0)
		{
			A[j+1] = A[j];
			j = j-1;
		}
		A[j+1] = Temp;
	}
	printf("\n\tTHE ASCENDING ORDER LIST IS...:\n");
	for(i=0; i<N; i++)
		printf("\n\t\t\t%d", A[i]);
	getch();
}

Download exe and source code here.

Sorting of numbers

Ranjith — Tue, 04 Nov 2008 20:04:34 +0000

Sorting means arranging a set of data in some order. There are different methods that are used to sort the data in ascending order. Some of the methods are

Selection sort
Bubble sort
Insertion sort

1. Selection sort

Here, to sort the data in ascending order, the 0th element is compared with all other elements. If it is greater than the compared element then they are interchanged. So after the first iteration smallest element is placed at the 0th position. The same procedure is repeated for the 1st element and so on. Read more…

2. Bubble sort

Here, to sort the data in ascending order, 0th element is compared with the 1st element. If it is greater than the 1st element then they are interchanged else remains same. Then 1st element is compared with 2nd element and procedure is continued. So after the first iteration largest element is placed at the last position. In the second iteration, the comparisons are made till the last but one position and now second largest element is placed at the second last position. After all the iterations, the list becomes sorted. Read more…

3. Insertion sort

Here, sorting takes place by inserting a particular element at the appropriate position. To sort the element in ascending order, in first iteration,1st element is compared with the 0th element. In the second iteration 2nd element is compared with 0th and 1st element. In general, in every iteration an element is compared with all the elements before it. While comparing if it is found that the element in question can be inserted at a suitable position, then space is created for it by shifting the other element one position to the right and inserting the element at the suitable position. This procedure is repeated for all the elements in the list. Read more…

In my program, you can enter 5 numbers which are to be sorted by any one of the above methods. After entering the numbers they are shown in red colour box and while comparison is done, the two elements which are compared are shown in green colour box. After sorting the elements, their permanent position is indicated by blue colour box. Click here to download the program.