学步园

#include <stdio.h>

void BubbleSort(int arr[],int n)
{
	int i,j,tmp;
	for(i=0;i<n-1;i++)
	{
		for(j=0;j<n-i-1;j++)
		{
			if(arr[j] > arr[j+1])
			{
				tmp = arr[j];
				arr[j] = arr[j+1];
				arr[j+1] = tmp;
			}
		}
	}
}

void SelectSort(int arr[],int n)
{
	int i,j,tmp;
	for(i=0;i<n-1;i++)
	{
		for(j=i+1;j<n;j++)
		{
			if(arr[i] < arr[j])
			{
				tmp = arr[i];
				arr[i] = arr[j];
				arr[j] = tmp;
			}
		}
	}
}


void insert_sort(int arr[],int n)
{
	int i,j,tmp;
	for(i=1;i<n;i++) 
	{
		tmp = arr[i];
		j = i-1; 
		while(tmp > arr[j])
		{
			arr[j+1] = arr[j];
			j--;
			if(j==-1)
				break;
		}
		
		arr[j+1] = tmp;
	}
}


int partitions(int arr[],int low,int high)
{
	int pivotkey = arr[low];
	while(low<high)
	{
		while(low < high && arr[high] >= pivotkey)
			--high;
		
		arr[low] = arr[high];

		while(low < high && arr[low] <= pivotkey)
			++low;

		arr[high] = arr[low];
	}
	arr[low] = pivotkey;
	return low;
}

void QuickSort(int arr[],int low,int high)
{
	int pivottag;
	if(low < high)
	{
		pivottag = partitions(arr,low,high);
		QuickSort(arr,low,pivottag-1);
		QuickSort(arr,pivottag+1,high);
	}
}


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

int main(void)
{
	int arr[] = {87,23,4,12,67,32};
	int n;
	n = sizeof(arr)/sizeof(int);

	printf("快速排序 (从大到小)\n");
	QuickSort(arr,0,n-1);
	print(arr,n);

	printf("-------------------------\n");


	printf("插入排序 (从大到小)\n");
	insert_sort(arr,n);
	print(arr,n);

	printf("-------------------------\n");

	printf("冒泡排序 (从小到大)\n");
	BubbleSort(arr,n);
	print(arr,n);

	printf("-------------------------\n");

	printf("选择排序 (从大到小)\n");
	SelectSort(arr,n);
	print(arr,n);


	return 0;
}