第二十三模板 11模板参数提供默认值 简单

//第二十三模板 11模板参数提供默认值
/*#include <iostream>
#include <string>
using namespace std;
//默认参数 class T2=int
template<class T1, class T2=int>
class People
{
public:
	T1 &getx();
	T2 &gety();
	T1 getx()const{ return x;}
	T2 gety()const{ return y;}
	People(const T1&a, const T2&b):x(a),y(b){ cout<<"构造函数执行"<<endl;}
private:
	T1 x;
	T2 y;
};

template<class T1, class T2>
T1&People<T1,T2>::getx()
{
    return x;
}
template<class T1, class T2>
T2&People<T1,T2>::gety(){
   return y;
}
int main()
{
	People<string>one[4]={
	   People<string>("hello world",5),
	   People<string>("good morning",6),
	   People<string>("sit down please",8),
	   People<string>("have a cup of tea",2)	
	};
	int num = sizeof(one)/sizeof(People<string,int>);
	cout<<"输出对像数组one的所有元素"<<endl;
	for(int i=0; i<num; i++){
		cout<<one[i].gety()<<"\t";
		cout<<one[i].getx()<<endl;
	}

	cout<<"修改one[3]的数据并输出"<<endl;
	one[3].getx()="gertie's fab eat";//有点不能理解，这里为什么能直接的用=赋值给getx呢
	one[3].gety()=6;
	cout<<one[3].gety()<<":\t";
	cout<<one[3].getx()<<endl;
}*/