// FILE: sequence2.h

// CLASS PROVIDED: sequence (part of the namespace main_savitch_4)

// There is no implementation file provided for this class since it is

// an exercise from Chapter 4 of "Data Structures and Other Objects Using C++"

//

// TYPEDEFS and MEMBER CONSTANTS for the sequence class:

// typedef ____ value_type

// sequence::value_type is the data type of the items in the sequence. It

// may be any of the C++ built-in types (int, char, etc.), or a class with a

// default constructor, an assignment operator, and a copy constructor.

//

// typedef ____ size_type

// sequence::size_type is the data type of any variable that keeps track of

// how many items are in a sequence.

//

// static const size_type DEFAULT_CAPACITY = _____

// sequence::DEFAULT_CAPACITY is the initial capacity of a sequence that is

// created by the default constructor.

//

// CONSTRUCTOR for the sequence class:

// sequence(size_t initial_capacity = DEFAULT_CAPACITY)

// Postcondition: The sequence has been initialized as an empty sequence.

// The insert/append functions will work efficiently (without allocating

// new memory) until this capacity is reached.

//

// MODIFICATION MEMBER FUNCTIONS for the sequence class:

// void resize(size_type new_capacity)

// Postcondition: The sequence's current capacity is changed to the

// new_capacity (but not less that the number of items already on the

// list). The insert/append functions will work efficiently (without

// allocating new memory) until this new capacity is reached.

//

// void start( )

// Postcondition: The first item on the sequence becomes the current item

// (but if the sequence is empty, then there is no current item).

//

// void advance( )

// Precondition: is_item returns true.

// Postcondition: If the current item was already the last item in the

// sequence, then there is no longer any current item. Otherwise, the new

// current item is the item immediately after the original current item.

//

// void insert(const value_type& entry)

// Postcondition: A new copy of entry has been inserted in the sequence

// before the current item. If there was no current item, then the new entry

// has been inserted at the front of the sequence. In either case, the newly

// inserted item is now the current item of the sequence.

//

// void append(const value_type& entry)

// Postcondition: A new copy of entry has been inserted in the sequence after

// the current item. If there was no current item, then the new entry has

// been appended to the end of the sequence. In either case, the newly

// inserted item is now the current item of the sequence.

//

// void remove_current( )

// Precondition: is_item returns true.

// Postcondition: The current item has been removed from the sequence, and the

// item after this (if there is one) is now the new current item.

//

// CONSTANT MEMBER FUNCTIONS for the sequence class:

// size_type size( ) const

// Postcondition: The return value is the number of items in the sequence.

//

// bool is_item( ) const

// Postcondition: A true return value indicates that there is a valid

// "current" item that may be retrieved by activating the current

// member function (listed below). A false return value indicates that

// there is no valid current item.

//

// value_type current( ) const

// Precondition: is_item( ) returns true.

// Postcondition: The item returned is the current item in the sequence.

//

// VALUE SEMANTICS for the sequence class:

// Assignments and the copy constructor may be used with sequence objects.

//

// DYNAMIC MEMORY USAGE by the List

// If there is insufficient dynamic memory, then the following functions

// throw a BAD_ALLOC exception: The constructors, insert, append.

#ifndef MYSEQUENCE_H

#define MYSEQUENCE_H

#include // Provides size_t

namespace DSProject01

{

class sequence

{

public:

// TYPEDEFS and MEMBER CONSTANTS

typedef double value_type;

typedef std::size_t size_type;

static const size_type DEFAULT_CAPACITY = 30;

// CONSTRUCTORS and DESTRUCTOR

sequence(size_type initial_capacity = DEFAULT_CAPACITY);

sequence(const sequence& source);

~sequence( );

// MODIFICATION MEMBER FUNCTIONS

void resize(size_type new_capacity);

void start( );

void advance( );

void insert(const value_type& entry);

void append(const value_type& entry);

void remove_current( );

void operator =(const sequence& source);

// CONSTANT MEMBER FUNCTIONS

size_type size( ) const;

bool is_item( ) const;

value_type current( ) const;

private:

value_type* data;

size_type used;

size_type current_index;

size_type capacity;

};

}

#endif

I need help implementing this. Thanks in Advance for any help that you can provide.