排序算法-归并排序

#include <iostream>
using namespace std;

void Msort(int a[], int start, int stop)
{
	if (stop - start > 1)
	{
		Msort(a, start, start + (stop - start) / 2);
		Msort(a, start + (stop - start) / 2+1, stop);
		int *temp = new int[stop - start + 1];
		int i = start;
		int j = start + (stop - start) / 2 + 1;
		int k = 0;
		while (i <= (start + (stop - start) / 2) && j <= stop)
		{
			if (a[i]<a[j])
			{
				temp[k] = a[i];
				i++;
			}
			else
			{
				temp[k] = a[j];
				j++;
			}
			k++;
		}
		while (i <= (start + (stop - start) / 2))
		{
			temp[k] = a[i];
			i++;
			k++;
		}
		while (j <= stop)
		{
			temp[k] = a[j];
			j++;
			k++;
		}
		for (int m = start; m <= stop; ++m)
		{
			a[m] = temp[m - start];
		}
	}
	else
	{
		if (a[start] > a[stop])
		{
			int temp = a[start];
			a[start] = a[stop];
			a[stop] = temp;
		}
	}
}

void main()
{
	int a[] = {2,6,12,1,8,7,2,3,7,5,4,5};
	Msort(a, 0, 11);
	for (int i = 0; i < 12; ++i)
	{
		cout << a[i] << endl;
	}
}