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Help With Template Class Declarations

luiscovar (14)
I'm getting this error "Error 1 error C2955: 'ONE' : use of class template requires template argument list " and i think it's because of something I'm missing in the friend function but I am not sure.

What does the error mean?

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#include <iostream>
#include <string>

using namespace std;

template <class T>
class ONE
{
private: T x,y;
public: ONE();
		ONE(T a, T b);
		void MaxMin (T& mx, T& mn);
		friend void Display(ONE P);
		~ONE();
};

template <class T>
ONE<T>::ONE()
{x=0, y=0;}

template <class T>
ONE<T>:: ONE(T a, T b)
{x=a, y=b;}

template <class T>
void ONE<T>::MaxMin(T& mx, T&mn)
{(x>y)?(mx=x, mn=y):(mx=y,mn=x);}

template <class T>
void Display(ONE P)
{cout<<"x=="<<P.x<<"\t"<<"y="<<P.y<<endl;}

template <class T>
ONE<T>::~ONE(){}

int main()
{
	ONE<int> r;
	ONE<string> s("Tom", "Adam");
	Display(r);
	Display(s);
	string max, min;
	s.MaxMin(max, min);
	cout<<"Maximum="<<max<<"\t"<<"Minimum="<<min<<endl;
system("pause");
return 0;
}
tath (408)
1. you should use template <typename T> instead of template <class T> in this case
2. 
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void Display(ONE P)
{cout<<"x=="<<P.x<<"\t"<<"y="<<P.y<<endl;}


should be void Display(ONE<T> P). Also this function is trying to access private members of class ONE. Make getters or make display class method.
luiscovar (14)
Ok, i changed it to template<typename T> but I'm still getting errors.

I haven't learn about getters or make display class method. Mind sharing a link where i can see how to do that?
tath (408)
changes are in bold font

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#include <iostream>
#include <string>

using namespace std;

template <typename T>
class ONE
{
private: T x,y;
public: ONE();
		ONE(T a, T b);
		void MaxMin (T& mx, T& mn);
		friend void Display(ONE P);
		~ONE();

//you need these to access private members liek x and y
        T getX(){return x;}
        T getY(){return y;}
};

template <typename T>
ONE<T>::ONE()
{x=0, y=0;}

template <typename T>
ONE<T>:: ONE(T a, T b)
{x=a, y=b;}

template <typename T>
void ONE<T>::MaxMin(T& mx, T&mn)
{(x>y)?(mx=x, mn=y):(mx=y,mn=x);}

template <typename T>
void Display(ONE<T> P)
{cout<<"x=="<<P.getX()<<"\t"<<"y="<<P.getY()<<endl;}

template <typename T>
ONE<T>::~ONE(){}

int main()
{
	ONE<int> r;
	ONE<string> s("Tom", "Adam");
	Display<int>(r);
	Display<string>(s);
	string max, min;
	s.MaxMin(max, min);
	cout<<"Maximum="<<max<<"\t"<<"Minimum="<<min<<endl;
system("pause");
return 0;
}
luiscovar (14)
Thank you for that. I will look more into getters but so far I seem to understand what you did.
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