The Borland Turbo C++ compiler which works
on Windows operating System, does not have all the capabilities of C++
programming. The core C++ compiler is present on Linux operating System. The
gcc is bundled with the compiler of C++ too. It is basically GNU C/C++ Compiler
Collection. You may use g++ compiler to compiler your C++ program file on
Linux.
Let's see, how to do it.
1. Open any text
editor such as gedit, vi, vim, or emacs and types your program in it. Save the
file with extension .cpp. It is required to identify that the file contains C++
code.
2. You need to write
this code in pure C++ format. Look at the program no.1, which is written for
Turbo C++ compiler and program no. 2 is written for gcc/g++ compiler.
#include<iostream.h>
class Add
{
public:
int
calculate(int a, int b)
{
return a +
b;
}
};
void main()
{
int x, y,
z;
Add a;
cout<<"Enter
two numbers: ";
cin>>x>>y;
z =
a.calculate(x, y);
cout<<"\nAddition
is: "<< z <<endl;
}
Program 1: Written for Turbo C++ Compiler.
#include<iostream> //Line-1
using namespace std; //Line-2
class Add
{
public:
int
calculate(int a, int b)
{
return a +
b;
}
};
int main() //Line-3
{
int x, y,
z;
Add a;
cout<<"Enter
two numbers: ";
cin>>x>>y;
z =
a.calculate(x, y);
cout<<"\nAddition
is: "<< z <<endl;
}
Program 2: Written for Linux g++ compiler.
3. Look at the changes
made in the second program, which is written for g++ compiler. In line number-1
#include<iostream> is written instead
of #include<iostream.h>. All C++ related
header files must be included in this fashion only. If C programming header
files such as stdio.h are required then these are included as usual
fashion such as #include<stdio.h>.
4. The Line-2 is an
extra line in program-2. It is pure C++ statement. In C++, namespaces allow to
group entities like classes, objects and functions under a name. This way the
global scope can be divided in "sub-scopes", each one with its own
name. The keyword 'using' is used to introduce a name from a namespace into the
current declarative region. All the files in the C++ standard library declare
all of its entities within the std namespace. That is why we have generally
included the using namespace std; statement in all programs that used any
entity defined in iostream.
5. The robust compiler
like g++ says that your main() function must return only 'int', it must not be
void. It is compulsory to return the int from main().
6. In order to compile
the program use command g++ on the terminal:
g++ add.cpp [Command-1]
7. It will compile the
file, check for the errors, prints on screen if any and generates an a.out
output file. The a.out is default output file name of g++ compiler. You may
change it by providing -o option to the command such as,
g++ add.cpp -o addition
[Command-2]
8. Now, this will
generate output executable file by name 'addition'.
Now execute the
file as,
./a.out [Command-1 output]
./addition [Command-2
output]
9. Your program will
get executed and generate output.
Enter two numbers: 56 41
Addition is: 97
