I have written a template class called Triple to take 3 objects of type T and I have three functions to get the min, max and median of these 3 objects.
I'm using the min and max functions from the STL to accomplish this.
I had to make all my methods const to get the max and min to work and it does work, with normal types, but then I created a class called Employee, this class has 2 functions getSalary() and the getName(), I'v overloaded the < > operators so I can use this class in my template.
This is where I run in to problems, the compiler is complaining with: const std::string Employee::getName(void)' : cannot convert 'this' pointer from 'const Employee' to 'Employee &'
I've tried changing everything to const in the employee class without success, and I cant get the triple class to work unless everything is const.
Where have I gone wrong?
Triple.h
#ifndef TRIPLE_H
#define TRIPLE_H
template<class T>
class Triple{
public:
Triple();
Triple(const T fE, const T sE, const T tE);
const T maximum();
const T minimum();
const T median();
private:
const T firstElement;
const T secondElement;
const T thirdElement;
};
#endif
Triple.CPP
#include "Triple.h"
#include <algorithm>
using std::max;
using std::min;
template<class T>
Triple<T>::Triple(){
}
template<class T>
Triple<T>::Triple(const T fE, const T sE, const T tE)
:firstElement(fE), secondElement(sE), thirdElement(tE){
}
template<class T>
const T Triple<T>::maximum(){
return max(max(firstElement, secondElement), thirdElement);
}
template<class T>
const T Triple<T>::minimum(){
return min(min(firstElement, secondElement), thirdElement);
}
template<class T>
const T Triple<T>::median(){
return max(min(firstElement, secondElement), min(max(firstElement, secondElement), thirdElement));
}
Employee.h
#include <string>
#include <iostream>
using std::ostream;
using std::string;
class Employee{
public:
Employee();
Employee(string, double);
const string getName();
double getSalary();
bool Employee::operator<(const Employee &rop);
bool Employee::operator>(const Employee &rop);
private:
double salary;
string name;
};
Employee.cpp
#include "Employee.h"
Employee::Employee(){
}
Employee::Employee(string nameIn, double salaryIn)
:name(nameIn), salary(salaryIn) {
};
const string Employee::getName(){
return name;
}
double Employee::getSalary(){
return salary;
}
bool Employee::operator < (const Employee &rop)
{
return (salary < rop.salary);
}
bool Employee::operator >(const Employee &rop)
{
return (salary > rop.salary);
}
main.cpp
#include "Triple.h"
#include "Triple.cpp"
#include "Employee.h"
#include <iostream>
using std::cout;
using std::endl;
int main(){
Employee john("John", 70000);
Employee tom("Tom", 30000);
Employee mark("Mark", 10000);
Triple<int> oneTriplet(1, 2, 3);
Triple<char> twoTriplet('A', 'B', 'C');
Triple<Employee> threeTriplet(john, tom, mark);
cout << oneTriplet.maximum() << endl;
cout << oneTriplet.minimum() << endl;
cout << oneTriplet.median() << endl;
cout << twoTriplet.maximum() << endl;
cout << twoTriplet.minimum() << endl;
cout << twoTriplet.median() << endl;
cout << threeTriplet.maximum().getName() << endl;
cout << threeTriplet.minimum().getName() << endl;
system("pause");
return(0);
}
