希尔排序

//分组 插入排序
//先分组 然后对每一组分别进行插入排序
//合组 然后再插入排序
//分组增量是：increasement/3+1
#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
#include<sys/timeb.h>
#include<time.h>
#define MAX 100
long getSystemTime(){
	struct timeb tb;
	ftime(&tb);
	return tb.time * 1000 + tb.millitm;
}
//插入排序：1.将无序序列插入到有序序列中
//交换函数
void Swap(int *a, int *b){
	int temp = *a;
	*a = *b;
	*b = temp;
}
//打印函数
void PrintArray(int arr[], int length){
	for (int i = 0; i < length; i++)
	{
		printf("%d ", arr[i]);
	}
	printf("\n");
}
void ShellSort(int arr[], int length){
	int increasement = length;
	int i,j,k;
	do
	{
		increasement = increasement / 3 + 1;
		for (int i = 0; i < increasement; i++)
		{
			for (int j = i+increasement; j < length; j+=increasement)
			{
				if (arr[j]<arr[j-increasement])
				{
					int temp = arr[j];
					for (k=j-increasement; k>=0&&temp<arr[k]; k-=increasement)
					{
						arr[k + increasement] = arr[k];
					}
					arr[k + increasement] = temp;
				}

			}
		}

	} while (increasement>1);
	
}
int main(void){
	int arr[MAX];
	srand((unsigned int)time(NULL));
	for (int i = 0; i < MAX; i++)
	{
		int randNum = rand() % MAX;
		arr[i] = randNum;
	}
	PrintArray(arr, MAX);
	long tshell_start = getSystemTime();
	ShellSort(arr, MAX);
	long tshell_end= getSystemTime();
	PrintArray(arr, MAX);
    printf("希尔排序时间%ld", tshell_end-tshell_start);
	system("pause");
	return 0;
}