01_冒泡排序

#include 
#include 
using namespace std;

//相邻元素进行比较 每一趟都有最大元素排好
template
void BubbleSort1(vector &a)  //经典冒泡排序 O(N^2)
{
	int i = 0;
	int j = 0;

	for(i = 0; i < a.size(); i++)
	{
		for (int j = 1; j < a.size()-i; j++) 
		{
			if (a[j-1] > a[j])
			{
				Comp tmp = a[j-1];
				a[j-1] = a[j];
				a[j] = tmp;
			}
		}
	}
}

template
void BubbleSort2(vector &a)   //优化冒泡排序
{
	int i = 0;
	int j = 0;
	int flag = 1;						//如果序列有序置0 无序置1

	for(i = 0; i < a.size() && flag; i++)   //如果序列有序 则不需要再排序
	{
		flag = 0;
		for (int j = 1; j < a.size()-i; j++) 
		{
			if (a[j-1] > a[j])				//如果前置元素比后置元素大 则交换位置
			{
				flag = 1;
				Comp tmp = a[j-1];
				a[j-1] = a[j];
				a[j] = tmp;
			}
		}
	}
}

void main()
{
	vector a;
	a.push_back(8);
	a.push_back(3);
	a.push_back(6);
	a.push_back(1);

	cout << "排序前：";
	for(int i = 0; i < a.size(); i ++)
		cout << a[i] << " ";
	cout << endl;

	BubbleSort1(a);
	cout << "排序后：";
	for(int i = 0; i < a.size(); i ++)
		cout <<  a[i] << " ";
	cout << endl;

	system("pause");
}