Tips|Tricks|Latest Gadgets|Freewares|Security

How To Block / Filter irritating Ads in Firefox

techdoon@gmail.com (TechDoon) — Thu, 14 Jun 2012 01:54:00 -0700

Advertisements are most of the time useless for us. Random Ads make us irritate. Ads consume lot's of our bandwidth too without having any reason. Now Firefox internet Browser offers us a intelligent add-on that enable it's users to filter/block unwanted adds. By adding Firefox add-on named AdBlock you can simply surf your desire contents. Just Follow these steps:
Step 1: Goto Add-On and search Adblock

Step 1:Or Goto Add-On Homepage

Step2 : Add to Firefox

Now Congratulation! You can enjoy Ads free internet Surfing...:)

Queues implementaion using link list in c++

techdoon@gmail.com (TechDoon) — Tue, 7 Feb 2012 05:37:00 -0800

Queue is a list of elements in which insertions are at one end of the list called rear end and the deletions are at the other end of the list called FRONT end.
Insertion is also known as Enqueue,deletion is also known as Dequeue.

  
    /******************************************************************************
Author: Sunil Kumar
Website: www.techdoon.com
Description: Queues implementaion using link list in c++
*******************************************************************************/
#include<iostream>
#include<cstdlib>
#include<memory>
using namespace std;
void menu();
struct node{
       int info;
       struct node *link;
       };
class queue{
      private:
                 struct node *front,*rear;
      public: 
             queue(); //constructor
             void insert(); //inserting element to the que
             void delet(); //removing elements from the que
             int isEmpty(); //Checking for empty
             void display(); //to fatch the data
       };
queue::queue() //constructor initializing variables
{
             front=rear=NULL;
              }
int queue::isEmpty()
{
               if(front==NULL)                                                   
                return 1;
                else
                return 0;
    }

void queue::insert()
{
     struct node *temp;
     int item;
     cout<<"\nITEM: "; cin>>item;
     temp=new node;
     temp->info=item;
     temp->link=NULL;
     if(front==NULL)
     {
                     front=temp;
                     }
                     else
                     {
                         rear->link=temp;
                         }
                         rear=temp;
     cout<<"\nNew item is inserted to the Queue!!!";
 }
 void queue::delet()
 {
      struct node *temp;
      int item,i;
      if((i=isEmpty())==1) cout<<"UNDERFLOW";
      else 
      {
           item=front->info;
           temp=front;
           front=temp->link;
           cout<<"\n "<<item<<"is Deleted.";
       }
  }
 int main()
 {
     menu();
     cin.get();
     return 0;
 }
void menu()
{
     queue obj;
     int ch;
     while(1)
     {
             cout<<"\n1.INSERT.\n2.DELETE.\n3.DISPLAY.\n0.EXIT.";
             cin>>ch;
             switch(ch)
             {
                       case 1: obj.insert();
                            break;
                       case 2: obj.delet();
                            break;
                       case 3:obj.display();
                       case 0:exit(0);
                       default:
                               cout<<"INVALID.";
                     }
             }
 
 }
void queue:: display()
{
    
     if(front==NULL){
                      cout<<"QUEUE is Empty.";
                      menu();
                      }
     else{
     while(front!=NULL){
     cout<<front->info<<"  ";
     front=front->link;
     }
     menu();
     }
 }

Queues implementaion using Array in c++

techdoon@gmail.com (TechDoon) — Tue, 7 Feb 2012 01:18:00 -0800

Queues are a type of container adaptor, specifically designed to operate in a FIFO context (first-in first-out), where elements are inserted into one end of the container and extracted from the other.

is a particular kind of abstract data type or collection in which the entities in the collection are kept in order and the principal (or only) operations on the collection are the addition of entities to the rear terminal position and removal of entities from the front terminal position.

/******************************************************************************
               Author: Sunil Kumar
               Website: www.techdoon.com
               Description: Queues implementaion using link list in c++
*******************************************************************************/
#include<iostream>
#include<cstdlib>
using namespace std;
void delet(int*);
void inser(int*);
class queue{
      private: 
               int *a;//array pointer
              int n,p,front, rear;/*n-total size allocated, 
              p-number of items inseted by user*/
      public:
             queue()//constructor to initialize the variables
             {
                  front=0;
                  rear=0;
              }
              ~queue();
             void delet();//for deletion of elements from que
             void inser(); //inserting elements to the que
             void getElemets(); //menu for user and memory allocation
      };
queue::~queue()
{
               delete a;
               }
int main() //program main function
{    
     queue obj;
     obj.getElemets();
    cin.get(); //pause screen
    return 0;
}
void queue::inser() //inserting item to the que
{
     //scan item
     int item,r;
     cout<<"\nITEM: ";
     cin>>item;
     //find rear to be insert
     
      if(front==1&&rear==n)//queuse is full
      {
           cout<<"OVERFLOW";
       }
       else{
     if(front==0) //queuse is empty
     {
                  front=1;
                  rear=1;
                 }
     else if(rear==n&&front!=1)
     {
          rear=1;
      }
      else
      {
          rear++;
      }
      a[rear]=item;
      }
     
   }
void queue::delet()
{
     if(front==0)cout<<"UNDERFLOW.";// queuse is enpty
     else
     {
         cout<<"ITEM="<<a[front];
     if(front==rear)
     {
                    front=0;
                    rear=0;
     }
     else if(front==n)
          {
          front=1;
      }
      else
      {
          front++;
      }
      }
 } 
void queue::getElemets()
{
     int ch; //except choice from menu
    cout<<"Enter number of item to be insert:";
    cin>>p;//number item user wants to enter
    n=p*2; //double size of number od elements
    a=new int(p*2); //arrar memory allocation
    cout<<"\nEnter Items:\n"; 
    for(int i=1;i<=p;i++)cin>>a[i]; //scanning elements from user
           front=1;
           rear=p;
    while(1)//infinite loop
    {
            cout<<"\n1.INSERT.\n2.DELETE.\n0.EXIT.";
            cin>>ch;
            switch(ch)
            {
                      case 1: inser();
                           break;
                      case 2: delet();
                           break;
                      case 0: exit(0);
                      default:
                              cout<<"INVALID";
                    }
           
           }
 }

Stack implementaion using link list in c++

techdoon@gmail.com (TechDoon) — Mon, 6 Feb 2012 05:08:00 -0800

In this post we have the representation of stack using a one-way linked list or singly linked list. The linked representation of a stack, commonly termed linked stack is a stack that is implemented using a singly linked list.

The INFO fields of the nodes hold the elements of the stack and the LINK fields hold pointers to the neighboring elements in the stack.
The start pointer of the linked list behaves as the top pointer variable of the stack and the null pointer of the last node in the list singles the bottom of the stack.

  
/******************************************************************************
Author: Sunil Kumar
Website: www.techdoon.com
Description: Stack implementaion using link list in c++
*******************************************************************************/

#include<iostream>
#include<cstdlib>
#include<memory>
using namespace std;
void menu();
class stack1
{
          public:
              int info;  //node data
              stack1 *link; // start node
              stack1(); //constructor for initialization
              void push();
              stack1* pop();
              stack1 getnode(); //memory allocation for new node 
      };
stack1 *top=NULL;
stack1::stack1()
{
                info=0;
                link=NULL;
                }
stack1* getnode()
{
       stack1 *tm;
       tm=new stack1;
       return tm;
       } 
void push(stack1* head)
{
     int item;
     cout<<"ITEM: "; cin>>item;
     head->info=item; //new node head's data initialiuzation
     head->link=top; //new node head's start initialize to top node 
     top=head; //top initialize to head address
 }
void pop()
{
     stack1 *tm;
     if(top!=0){
                       cout<<"\nPOP Element is "<<top->info;
                       tm=top;// getting top to tm to make it free
                       top=top->link; //top initialize to next
                       free(tm);
                       }
     else cout<<"\nStack UNDERFLOW.";
 }
int main()
{
    menu();
    return 0;
}
void menu()
{
     int ch;
     stack1 *temp;
     while(1){
     cout<<"\n1.PUSH.\n2.POP.\n0.EXIT."; cin>>ch;
     switch(ch)
     {
               case 1:temp=getnode(); 
                    if(temp!=NULL)push(temp);
                    else cout<<"Stack OVERFLOW.";
                    break;
               case 2:pop();
                      break;
               case 0: exit(0);
               default:
                       cout<<"INVALID";
                       break;
               }
               }
 }

Stack Implementaion in C++

techdoon@gmail.com (TechDoon) — Mon, 6 Feb 2012 00:19:00 -0800

A stack is a last in, first out (LIFO) abstract data type and linear data structure. A stack can have any abstract data type as an element, but is characterized by only three fundamental operations: push, pop and stack top. The array implementation aims to create an array where the first element (usually at the zero-offset) is the bottom.
In this source code I have implemented Push and Pop function through C++ by using classes, It is easy to understand and implement, each line code have its description along it.

***************************************************************
 Author: Sunil Kumar
 Web: www.techdoon.com
 Description: C++ Program implement a stack using an array
***************************************************************/
# include<iostream>
# include<cstdlib>
# define SIZE 20
using namespace std;
class stack
{
      private:
              int a[SIZE];
              int top; // Top of Stack
      public:
            stack();
           void push();
           int pop();
           int isEmpty();
           int isFull();
};
stack::stack()
{
              top=0;
}
int stack::isEmpty() //check stack for underflow
{
 return(top==0?1:0);   
}
int stack::isFull() //check stack overflow
{
    return(top==SIZE?1:0); 
}
void stack::push()//insert item
{
    int item;
    if(!isFull()){
                  cout<<"\nITEM:"; cin>>item;
                  a[top]=item;
                  top++;
         }
    else{
         cout<<"Stack OverFlow Error.";
         }
    }
int stack::pop() //pop item
{
    if(!isEmpty()){
                   return(a[--top]);
                   }
    else{
         cout<<"Stack Underflow Error.";
         }
}
int main()
{
    stack s;
    int n,i=1;
    cout<<"No. Of item you want to push:\n";
    cin>>n;
   while(i<=n)
    {
    s.push();
    i++;
    }
    cout<<s.pop()<<endl;
    system("PAUSE"); //pause output screen
    return 0;
}

Recover ROOT Password without OLD password in UBUNTU (Linux System )

techdoon@gmail.com (TechDoon) — Thu, 2 Feb 2012 10:58:00 -0800

In UBUNTU one of the biggest problem is that whenever we installs it, Ubuntu makes us ordinary user of the system by default. But whenever you needs to make any major changes to system it asks you for root authentication. At that time you need ROOT password, and if you doesn't have it, you are not to permitted to make changes to it.
Here is the solution of this problem by following these simple steps you can easily recover your Root Password or you can Login as ROOT.
1.Simply BOOT your system in RECOVERY MODE (with the help of up-down -> ).

2.Select REMOUNT.

Set your password as shown in above image by using key word 'passwd'. //here error will occur so look 4 step.
3. Select root -> Drop to root shell prompt.

4Change your password and Resume Booting.

Now all done...You can login as ROOT with your new password.

Login As ROOT in FEDORA (Linux System) without password

techdoon@gmail.com (TechDoon) — Thu, 2 Feb 2012 10:31:00 -0800

Today here, I am going to give you a top secret and one of the best hidden feature of FEDORA Operating System. Now after reading this article you may not need to worry anymore about your lost or forgotten passwords of your root account. Or maybe you can use it for any intentional proposes.

Here are the basic steps that enable you to login as ROOT to FEDORA Operating System without any kind of password.

FEDORA have multiuser supporting feature, but at the time of login as root in this tutorial we will make to login as Single User that will be ROOT only.

GRUB: a Grub is a boot loader for Linux Systems.

Here with the help of grub we are going to solve our problem:

Step 1: Here press 'e' to go to grub edit mode as shown below:

Step 2: Now Again press 'e ' to go to Kernel edit mode.

Step 3: Write 'linux single ' at last line.

Step 4: Press ENTER to back and save.

Step 5: Press 'b' to book as ROOT.

After Reboot you are at ROOT Terminal, in single mode, At terminal you can reset your password.

Now all done..enjoy it... have a good time.

Install And Configure Apache In Ubuntu

techdoon@gmail.com (TechDoon) — Mon, 30 Jan 2012 00:18:00 -0800

Hey guess what? Here is a brief tutorial to install and configure Apache Server at your UBUNTU system. If you’re wishing to have a web server on your own system just follow below steps and defiantly you will have a web server on your system free and most popular one. One big fact I want to tell you that Apache is a one of the most used World Wide Web server; in fact it is about 70%.

Note: Apache is one of the important Module of LAMP (Linux, Apache2, MySQL, PHP5).

Here we go:

INSTALLATION OF APACHE2

Just open your Terminal

sudo apt-get install apache2

Wait for few minutes.

Congrats you did it, man…!!

Now go to your any web browser “http://localhost”. You can see its working

CONFIGURATION OF APACHE2

START:

sudo /etc/init.d/apache2 start #start apache

STOP:

sudo /etc/init.d/apache2 stop #stop apache

RESTART:

sudo /etc/init.d/apache2 restart #restart apache

All done……Enjoy the Hosting.