How to create templates in c++ and do generic programming.

1. Templates in C++
CREATED BY – MAYANK BHATT

2. Contents
• Templates
• Function templates
• Class templates
• Applictaions of templates

3. Templates
• Templates are the foundation of generic
programming, which involves writing code in a
way that is independent of any particular type.
• We can use templates to define functions as well
as classes

4. Function Templates
• There are several functions of considerable importance
which have to be used frequently with different data
types.
• The limitation of such functions is that they operate only
on a particular data type.
• It can be overcome by defining that function as a
function template or generic function.
• Syntax:
template <typename parameter, …..>
returntype function_name (arguments)
{
…… // body of template function
……
}

5. Example Program:
• #include<iostream>
• #include<conio.h>
• using namespace std;
• template <class t>
• t mymax(t a,t b)
• { return(a>b?a:b);
• }

6. • main()
• { int a,b;
• float c,d;
• cout<<"Enter two integers:n";
• cin>>a>>b;
• cout<<"nMax="<<max(a,b);
• cout<<"nEnter two floating point numbers:n";
• cin>>c>>d;
• cout<<"nMax="<<max(c,d);
• getch();
• }

7. Output:

8. Class Templates
• Class can also be declared to operate on different data types.
Such class are called class templates.
• A class template specifies how individual classes can be
constructed similar to normal class specification.
• These classes model a generic class which support similar
operations for different data types.
• Syntax :
template <class T1, class T2, …..>
class class_name
{
T1 data1; // data items of template type
void func1 (T1 a, T2 &b); // function of template
argument
T func2 (T2 *x, T2 *y);
}

9. • #include<iostream>
• #include<conio.h>
• using namespace std;
• template <class t>
• class mypair
• { private: t a,b;
• public: mypair(t first,t second)
• {a=first;
• b=second;
• }
• t getmax();
• };

10. • template <class t>
• t mypair<t>::getmax()
• {return(a>b?a:b);
• }
• main()
• {
• mypair<int> myints(100,275);
• mypair<float> myfloat(1.7777,1.7778);
• cout<<"max integer="<<myints.getmax();
• cout<<"nmax float="<<myfloat.getmax();
• getch();
• }

11. Output:

12. Applications of Templates
• Templates support generic programming, which
allows to develop reusable software
components such as function, class, etc.
• Supporting different data types in a single
framework.
• A template in C++ allows the construction of a
family of template functions and classes to
perform the same operation on different data
types.
• It allows a single template to deal with a generic
data type T.