作业

#include<iostream>
class meter{};
class kilometer{};
class second{};
class minute{};
template <typename T> 
struct traits_help
{
    static const int radix = 1;
    static const char unit = '\0'; 
};
template <> 
struct traits_help<meter>
{
    static const int radix = 1; 
    static const char unit = 'm'; 
};
template <> 
struct traits_help<kilometer>
{
    static const int radix = 1000; 
    static const char unit = 'm'; 
};
template <> 
struct traits_help<second>
{
    static const int radix = 1;
    static const char unit = 'm'; 
};
template <> 
struct traits_help<minute>
{
    static const int radix = 60;
    static const char unit = 's'; 
};

template <typename T>
class Measurement 
{
private:
    int value;
public:
    Measurement(int value){
        this->value = value;
    }
    Measurement& operator = (const int value)
   {
       this->value = value;
       return *this;
    }
    void description()
    {
        std::cout<<this->value*traits_help<T>::radix;
        std::cout<<traits_help<T>::unit<<std::endl;
    }
};

int main()
{
    Measurement<meter> m1 = 10;
    Measurement<kilometer> m2 = 10;
    Measurement<second> m3 = 20;
    Measurement<minute> m4 = 20;
    Measurement<int> m5 = 20;
    m1.description();
    m2.description();
    m3.description();
    m4.description();
    m5.description();
    return 0;
 }