C++中模板的使用示例

#include<iostream>
using namespace std;

template<typename T> //将Point设为模板，这样Point类中的就可以是int型或者double型
class Point
{
public:
T x, y;
Point(T x = 0, T y = 0) :x(x), y(y){}
};

template<typename T>
Point<T> operator + (const Point<T>& A, const Point<T>& B)
{
return Point<T>(A.x + B.x, A.y + B.y);
}

template<typename T>
ostream& operator << (ostream &out, const Point<T>& p)
{
out << "(" << p.x << "," << p.y << ")";
return out;
}

template<typename T>
T sum(T* begin, T* end)
{
T ans = 0;
for (T* p = begin; p != end; p++)
{
ans = ans + *p;
}
return ans;
}

int main()
{
Point<int> a(1, 2), b(3, 4);
Point<double> c(1.1, 2.2), d(3.3, 4.4);
cout << a + b << " " << c + d << endl;
Point<int> e[] = { Point<int>(1, 2), Point<int>(3, 4), Point<int>(5, 6), Point<int>(7, 8) };
cout << sum(e, e + 4) << endl;//Point数组求和
return 0;
}