Program Of Ten Random Numbers

#include <stdio.h>

#include <iostream.h>

#include <stdlib.h>

#include <values.h>

#include <time.h>

void main()

{

int i,j,k,l,list[1000];

FILE *fp;

char any[8];

cout << "Enter a file name\n";

cin >> any;

fp = fopen(any,"wb");

    

for(j=0;j<50;j++)

    {

     

  for(i=0;i<200;i++)

    

   {

 

 k = rand() % RAND_MAX;

  

fwrite(&k,sizeof(int),1,fp);

       }

    }

    i = 0;

   

 while (fread(&l,sizeof(int),1,fp) != 0)

    {

 

 list[i] = l;

 i = i + 1;

    }

fclose(fp);

for (i=0;i<50;i++)

    

cout << list[i] << '\n';

}

Program Of Pure Virtual Function In C++

#include< iostream.h>

#include< conio.h>

class abc

{

protected :

int a,b;

public:

void take()

{ 

cout<< "\nEnter two 'int' values::";

cin>>a>>b;

} 

virtual void display()=0; 

}; 

class xyz:public abc

{

public:

void display()

{

cout<< "\nSum for 1st derived class="<< a+b;

}

};

class mn:public abc

{

public:

void display()

{

cout<< "\nSum for 2nd derived class:"<< a+b;

}

};

void main()

{

clrscr();

xyz ob;

mn ob1;

abc *ptr;

ptr=&ob;

cout<< "\nFor object of 1st derived class."<< endl;

ptr->take();

ptr->display();

cout<< "\nFor object of 2nd derived class."<< endl;

ptr=&ob1;

ptr->take();

ptr->display();

getch();

}

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Pure  Virtual Function

In object-oriented programming, a  virtual method is a function or method whose behaviour can be overridden within an inheriting class by a function with the same signature. This concept is a very important part of the polymorphism portion of object-oriented programming (OOP).

by:---http://en.wikipedia.org/wiki/Virtual_function