最大最小值算法

InputIterator min_element (InputIterator beg, InputIterator end);
InputIterator min_element (InputIterator beg, InputIterator end, CompFunc op);
InputIterator max_element (InputIterator beg, InputIterator end);
InputIterator max_element (InputIterator beg, InputIterator end, CompFunc op);

功能：

所有这些算法都返回区间[beg, end)中的最大或最小值的位置

备注：
a、上述无op参数版本以operator<进行元素比较
b、op用来比较两个元素：op(elem1, elem2)如果第一个元素小于第二个元素，应当返回true
c、如果存在多个最大或最小值，上述算法返回找到的第一个最大或最小值
d、op不应该改动传进去的参数

e、时间复杂度：线性

class CPeople
{
	int m_nAge;
	string m_strName;
public:
	CPeople(int nAge= 0) :m_nAge(nAge){}
	CPeople(int nAge, string strName):m_nAge(nAge),m_strName(strName){}
	int get_age() { return m_nAge; }
	string get_name() { return m_strName; }
	friend ostream& operator<<(ostream &ouput, CPeople people);
};

ostream & operator<<(ostream &output , CPeople people)
{
	output << people.get_name() << " " << people.get_age() << endl;
	return output;
}

bool compare(CPeople people1, CPeople people2)
{
	if (people1.get_age() < people2.get_age())
		return true;
	return false;
}

int main(int argc, char *argv[])
{
	CPeople arrPeople[] = {CPeople(20,"乔峰"),CPeople(15,"段誉"),CPeople(33,"赵敏"),CPeople(80,"虚竹"),CPeople(7,"白眉大侠"),CPeople(18,"周芷若"),CPeople(50,"南慕容")};
	vector<CPeople> vec1(arrPeople, arrPeople + sizeof(arrPeople)/sizeof(arrPeople[0]));
	
	// 查找最小值
	vector<CPeople>::const_iterator iterVec = min_element(vec1.begin(),vec1.end(), compare);
	if (iterVec != vec1.end())
	cout << *iterVec;

	// 查找最大值
	vector<CPeople>::const_iterator iterVec1 = max_element(vec1.begin(),vec1.end(), compare);
	if (iterVec1 != vec1.end())
		cout << *iterVec1;
	return 0;
}