排序算法之选择排序

<pre name="code" class="cpp">// SelectSort.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include "iostream"

using namespace std;

//   说明：排序算法 - 每一次迭代中都选择最小的数
void SelectSort(double a[], int n)
{
	for (int i=0; i<n; i++)
	{
		int iMin = i; 
		for (int j=i + 1; j<n; j++)
		{
			if (a[j] < a[iMin])
			{
				iMin = j;
			}
		}

		if (iMin != i)
		{
			double dTemp = a[i];
			a[i] = a[iMin];
			a[iMin] = dTemp;
		}
	}
}


int _tmain(int argc, _TCHAR* argv[])
{
	double a[] = {2.0, 5.4, 4.0, 8.0, 3.0, 5.0, 1.0, 9.0, 7.0};
	int n = sizeof(a) / sizeof(*a);

	cout<<"排序前：\n";
	for each (double x in a)
	{
		cout<<x<<" ";
	}
	cout<<endl;

	SelectSort(a, n);

	cout<<"排序后：\n";
	for each (double x in a)
	{
		cout<<x<<" ";
	}
	cout<<endl;

	return 0;
}