Insertion Sort

An element which is to be 'insert'ed in this sorted sub-list, has to find its appropriate place and then it has to be inserted there. Hence the name, insertion sort.

The array is searched sequentially and unsorted items are moved and inserted into the sorted sub-list (in the same array). This algorithm is not suitable for large data sets as its average and worst case complexity are of Ο(n²), where n is the number of items.

Algorithm OF Insertion_Sort

Insertion_sort (A)

For (j=2 to a.length)

{

Key=a[j];

I=j-1;

While(i>=0 and a[i]>key)

{

A[i+1]=a[i];

I=i-1;

}

A[i+1]=key;

}

Program Of Insertion Sort

#include <stdio.h>

int main()

{

  int n, array[1000], c, d, t;

  printf("Enter number of elements\n");

  scanf("%d", &n);

  printf("Enter %d integers\n", n);

  for (c = 0; c < n; c++) {

    scanf("%d", &array[c]);

  }

  for (c = 1 ; c <= n - 1; c++) {

    d = c;

    while ( d > 0 && array[d] < array[d-1]) {

      t          = array[d];

      array[d]   = array[d-1];

      array[d-1] = t;

      d--;

    }

  }

  printf("Array sorted by insertion sort technic is :\n");

  for (c = 0; c <= n - 1; c++) {

    printf("%d\n", array[c]);

  }

  return 0;

}

output Of Program:-