n個人報數退出問題，數到m退出,最後剩下的是幾號

#include "stdafx.h"
#include "iostream"
using namespace std;

int last_people(int n,int m)
{
	int *p = new int[n];
	for (int i = 0;i < n; i ++)//編號//
		*(p+i) = i + 1;
	int k = 0,out_of_line = 0;
	int i =0;
	int last;
	while(out_of_line < n-1)//退出人數<n-1//
	{
		
		if (*(p+i) != 0)//報數//
			k++;
		if (k == m)
		{
			k = 0;
			*(p+i) = 0;
			out_of_line++;
		}
		i++;
		if (i == n)//環//
			i = 0;
	}
	i = 0;
	while(*(p+i) == 0)
		i++;
	last = *(p+i);
	delete []p;
	p = NULL;
	return last;
}

</pre><pre code_snippet_id="262733" snippet_file_name="blog_20140328_1_7653492" name="code" class="cpp">int _tmain(int argc, _TCHAR* argv[])
{
	cout<<last_people(20,7)<<endl;
	return 0;
}