C语言 | 栈的应用 | 非递归栈实现快排

/* 非递归栈实现快排 */
#include <stdio.h>
#include <math.h>>
#include <malloc.h>
#include <windows.h>

typedef struct _Stack
{
	int *data;
	int top;
}Stack;

/* 一次快排的结果，返回基准的位置 */
int OneQuickSort(int *arr, int i, int j)
{
	//②if(j - i < 1)  return -1;
	int tmp = arr[i];		//基准
	while( i < j )
	{
		while( i < j )
		{
			if(arr[j] < tmp) break;
			j--;
		}
		arr[i] = arr[j];		//向前移动 

		while(i < j)
		{
			if(arr[i] > tmp) break;
			i++;
		}
		arr[j] = arr[i];		//向后移动
	}
	arr[i] = tmp;	//j == i
	return i;
}

void QuickSort(int *arr, int left, int right)
{
	Stack st;
	//栈的长度最长不超过 log2(n)
	int size = (int)log10(right-left+1)/log10(2.0);
	size = (size+1)*sizeof(int);
	st.data = (int*)malloc(size);
	st.top = 0;
	//入栈
	st.data[st.top++] = left;
	st.data[st.top++] = right;

	//循环模拟递归
	while(st.top != 0)
	{
		/* 出栈 快排 */
		right = st.data[--st.top];
		left = st.data[--st.top];	

		int mod = OneQuickSort(arr, left, right);

		//与基准的紧挨着，为有序状态
		if(mod - left > 1)	//②if(mid != -1)
		{
			st.data[st.top++] = left;
			st.data[st.top++] = mod - 1;
		}
		if(right - mod > 1)
		{
			st.data[st.top++] = mod + 1;
			st.data[st.top++] = right;
		}
	} 

	free(st.data);
} 

测试

int main()
{
	int arr[] = {1,54,6,6,748,768,7,64,6379,76,78,746,7,64};

	QuickSort(arr, 0, sizeof(arr)/sizeof(arr[0]) - 1);

	int len = sizeof(arr)/sizeof(arr[0]);

	for(int i = 0; i < len; i++)
	{
		printf("%d  ",arr[i]);
	}

	system("pause");
	return 0;

}

截图：