Example to show the difference between struct and class in C++

This is a very simple example showing the difference between struct and class in C++. In reality there is hardly any difference between struct and class in C++. They are exactly the same except that the default is public in struct and private in class. You can do everything you can do in a class in a struct but its not a good practice. The reason being struct's are inherited from C programming and as the name suggests it was meant to represent a structure. You can also read the C++ FAQ that explains it better.

//Program tested on Microsoft Visual Studio 2008 - Zahid Ghadialy
//This very simple example demonstrates the basic difference 
//between struct and class in C++

#include<iostream>

using namespace std;

class A {
  int a; //default in class is private

public:
  int b;
  void initVariables(int c1, int c2, int c3)
  {
    a=c1, b=c2, c=c3;
  }
  void printVariables()
  {
    cout<<"a = "<<a<<"    b = "<<b<<"    c = "<<c<<endl;
  }

private:
  int c;
};

struct B {
  int a; //default in struct is public

public:
  int b;
  void initVariables(int s1, int s2, int s3)
  {
    a=s1, b=s2, c=s3;
  }
  void printVariables()
  {
    cout<<"a = "<<a<<"    b = "<<b<<"    c = "<<c<<endl;
  }

private:
  int c;
};

int main()
{
  A var1;
  var1.initVariables(10, 11, 12);
  //var1.a = 15; //Cant be changed as its private
  var1.b = 16;
  //var1.c = 17; //Cant be changed as its private
  cout<<"Printing the variables from the class"<<endl;
  var1.printVariables();

  B var2;
  var2.initVariables(20, 21, 22);
  var2.a = 25; //possible
  var2.b = 26;
  //var2.c = 27; //Cant be changed as its private
  cout<<"\n\nPrinting the variables from the struct"<<endl;
  var2.printVariables();
  cout<<"\n\n";

  return 0;
}

The output is as follows: