冒泡排序 优化

// BubbleSort.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"


void Swap(int &a, int &b)
{
	int itmp;
	itmp = a;
	a = b;
	b = itmp;
}

void BubbleSort(int a[], int n)
{
	int i,k,j;
	k = n;

	for ( i = 0; i < k; i++)
		for ( j = 1; j < k - i; j++)
		{
			if (a[j-1] > a[j])
			{
				Swap(a[j-1], a[j]);
			}
		}
}


void BubbleSort1(int a[], int n)
{
	int k, j;
	bool flag = true;
	k = n;

	while (flag)
	{
		flag = false;
		for ( j = 1; j < k; j++ )
		{
			if (a[j-1] > a[j])
			{
				Swap(a[j-1], a[j]);
				flag = true;
			}
		}
		k--;
	}
}

void BubbleSort2(int a[], int n)
{
	int j, k;
	int flg = n;
	k = n;

	while(flg > 0)
	{
		k = flg;
		flg = 0;
		
		for ( j =  1; j < k; j++)
		{
			if (a[j-1] > a[j])
			{
				Swap(a[j-1], a[j]);
				flg = j;
			}
		}
	}
}

int _tmain(int argc, _TCHAR* argv[])
{
	int a[10]= {1,3,2,4,7,8,9,5,6,0};

//	BubbleSort(a, 10);
//  BubbleSort1(a, 10);
	BubbleSort2(a, 10);

	for ( int i = 0; i < 10; i++)
	{
		printf("%d ", a[i]);
	}
	printf("\n");

	return 0;
}