用C语言写一个希尔排序

希尔排序（Shell Sort）是一种插入排序，它是1959年由Donald Shell发明的。它的基本思想是将数组分割成多个子序列，然后对子序列进行插入排序。

以下是C语言实现的希尔排序算法：

void shellSort(int arr[], int n)
{
// Start with a big gap, then reduce the gap
for (int gap = n/2; gap > 0; gap /= 2)
{
// Do a gapped insertion sort for this gap size.
// The first gap elements a[0..gap-1] are already in gapped order
// keep adding one more element until the entire array is
// gap sorted
for (int i = gap; i < n; i += 1)
{
// add a[i] to the elements that have been gap sorted
// save a[i] in temp and make a hole at position i
int temp = arr[i];

// shift earlier gap-sorted elements up until the correct
// location for a[i] is found
int j;
for (j = i; j >= gap && arr[j - gap] > temp; j -= gap)
arr[j] = arr[j - gap];

// put temp (the original a[i]) in its correct location
arr[j] = temp;
}
}
}