NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c++-part2/13777

Text File | 1996-08-05 | 4.4 KB | 111 lines

Path: ix.netcom.com!chi-il9-08
From: [e-mail]
Newsgroups: comp.lang.c++
Subject: Re: [Q] Working through C++ - some help needed
Date: 27 Mar 1996 04:50:33 GMT
Organization: Netcom
Message-ID: <4jahep$[e-mail]>
References: <[e-mail]>
NNTP-Posting-Host: chi-il9-08.ix.netcom.com
X-NETCOM-Date: Tue Mar 26 10:50:33 PM CST 1996
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In article <[e-mail]>, access <[e-mail]> wrote:
>Working my way through the "forest" of C++, I try to work on an exercise
>that is more like invented, than a proven workable problem - but I
>thought of being of help in understanding different concepts in C++. I am
>trying to build the followings (based on classes, rather than one
>single lenghty algorithm):
>- An array list (having the regular functions, like the ones shown
>everywhere in the books: get, put, moveto, gotostart, gotoend, etc.),
>which will contain a different queue in each of its elements, queues
>being distinguished by a number (with pop and push functions, at least)
>which queue will contain nodes (... remember the Russian dols :-) ...),
>and each node will contain a couple of the most significant elements of
>C++ (a char, an int, a string, for example).
>Now, being said the above, I don't know how to start building and how to
>access the elements of each node (I don't even know if it is possible)
>either by user input or from a file. What I try actually would be
>something like: given an element with the int as the array element where
>its queue is to be placed, how do I actually put it there using the
>normal messages such constructions would come with (like: read the whole
>element from a file as a string which has the data separated by blanks -
>int, char and string, then taking the int and deciding what element in
>the array it is going to go into, then taking the char and the string and
>building the actual element and attaching it to the queue in the decided
>array element). Did anybody make any sense out of this? If the answer is
>YES, would any kind soul enlighten me on whether this would be possible
>to build, and actually how to manipulate the messages of the different
>classes I see being built (class array_list, class My_queue and class
>My_queue_node) to put/remove the elements?
>Thanks a lot to whoever had the patience to read through this lenghty and
>senseless message, and mostly to whoever would care to answer me if this
>is "mission impossible".
>
>Sleepless_C++

That's an interesting subject (for a beginner, like myself). I will "bite":

What about the following classes:

class My_elem_in_node
{private: int my_number;
      char my_char;
      char *my_strg_ptr;
public:  int get_my_number ();
     char get_my_char();
     char *get_my_strg();
     // a constructor
     // a destructor
     void set_my_number (int &new_number) const;
     void set_my_char (char &new_char) const;
     void *set_my_strg (char *new_strg); }

template <my_type_above>
class My_queue_node
{private: My_queue_node (const my_type_above &new_element, My_queue_node
*next_ptr)
public: my_type_above node_element;
    My_queue_node *next;
friend class My_queue <my_type_above>; }

template <class my_type_above>
class My_queue
{public: My_queue();
     ~My_queue();
     void enqueue (const my_type_above &new_node)
     my_type_above dequeue();
     // others, like clear(), isempty(), isfull(), display(), etc.
private: My_queue_node <my_type_above> *head, *tail; }

template <class my_type_above>
class my_array
{public: my_array (int max_nb_of_elements = 10);
     ~my_array();
     void insert (const my_type_above &new_array_element);
     void remove ();
     // and others (perhaps a clear (), is_empty(), is_full(), etc.)
private: int max_array_size;
     int size_array;
       int cursor; // to go through array
     my_type_above *array_element; }

class strg_manipulator // for whatever string you're getting from a file/user
{private: char *strg_content;
public:   strg_manipulator (char *string_in = 0);
      ~strg_manipulator ();
      char *get_user_strg ();
      void *set_user_strg (char *string_in); }

For sure other classes will fit here, like file I/O processing (read, save),
etc.
I hope this helps, but definitely doesn't fully answer your question. I told
you I am a beginner myself :-). Perhaps somebody will care to correct or
complete me with how to put these pieces together.

PS - You might want to check your e-mail address - it bounces back when I try
to e-mail you.

Cheers,
Stefan