## C, sort, binary_insertion_sort.c

``````/* Sorting of array list using binary insertion sort
* Using binary search to find the proper location for
* inserting the selected item at each iteration. */
#include <stdio.h>
#include <stdlib.h>

/*Displays the array, passed to this method*/
void display(int *arr, int n)
{
int i;
for (i = 0; i < n; i++)
{
printf("%d ", arr[i]);
}
printf("\n");
}

int binarySearch(int *arr, int key, int low, int high)
{
if (low >= high)
return (key > arr[low]) ? (low + 1) : low;
int mid = low + (high - 1) / 2;
if (arr[mid] == key)
return mid + 1;
else if (arr[mid] > key)
return binarySearch(arr, key, low, mid - 1);
else
return binarySearch(arr, key, mid + 1, high);
}
/*This is where the sorting of the array takes place
arr[] --- Array to be sorted
size --- Array Size
*/
void insertionSort(int *arr, int size)
{
int i, j, key, index;
for (i = 0; i < size; i++)
{
j = i - 1;
key = arr[i];
/* Use binrary search to find exact key's index */
index = binarySearch(arr, key, 0, j);
/* Move all elements greater than key from [index...j]
* to one position */
while (j >= index)
{
arr[j + 1] = arr[j];
j = j - 1;
}
/* Insert key value in right place */
arr[j + 1] = key;
}
}

int main(int argc, const char *argv[])
{
int n;
printf("Enter size of array:\n");
scanf("%d", &n);  // E.g. 8

printf("Enter the elements of the array\n");
int i;
int *arr = (int *)malloc(n * sizeof(int));
for (i = 0; i < n; i++)
{
scanf("%d", &arr[i]);
}

printf("Original array: ");
display(arr, n);

insertionSort(arr, n);

printf("Sorted array: ");
display(arr, n);

free(arr);
return 0;
}
``````