c++ 删除整形数组中重复的数字

int *RemoveDup(int arr[], int n)
{
	int *tmp = NULL;
	int *arr_new = NULL;
	arr_new = (int *)malloc(n*sizeof(int));
	tmp = arr_new;
	set<int> s;
	pair<set<int>::iterator, bool> p;
//	list<int> l; 用list也可以保存
	int k = 0;
	for (int i=0;i<n;i++)
	{
		p=s.insert(arr[i]);
		if (p.second)
		{
//			l.push_back(arr[i]);
			*tmp = arr[i];
			k++;
			tmp++;
		}
	}
	*tmp='\0';
	
	return arr_new;
	
}

int _tmain(int argc, _TCHAR* argv[])
{
	int arr[12]={11,12,13,14,15,16,17,18,19,17,18,20};
		
	int *res = NULL;
	res = RemoveDup(arr,12);
	while(*res)
	{
		printf("%d\n",*res);
		res++;
	}
	system("pause");
	return 0;
}