Here is the code,
Code:
	vector<int> vec;

	for(int i=0;i<10;++i)
		vec.push_back(i);

	random_shuffle(vec.begin(), vec.end());

	nth_element(vec.begin(), vec.begin()+7, vec.end());
No matter how I choose the second argument passed to nth_element, the elements in vec are always sorted as,
0,1,2,3,4,5,6,7,8,9
What is the use of second argument here?Thanks.