I've got a program to do for a class I'm taking. I've got most the code written but I can't get the two classes to play together like I want them to.
Here is the relavent part of the assignment:
Quote:
A concordance is an alphabetical listing of all words in a text
with a list associated with each word of the line numbers in which the
word appears
Design and implement two C++ classes for linked lists (see below).
Design, code and test a C++ program using the linked lists that
reads a text file (using file redirection) and generates a concordance of
all the words from that text.
You will need a linked list of strings and linked list of numbers, Each
node of the string list must point to a list of numbers.
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One class, wordlist, uses the other class numlist to keep a list of line numbers in which a certain word was found. When I test both classes alone, they work as I think they should, but when I try to use numlist called from wordlist, it only remembers the first line number inserted when you put the same word in.
wordlist.h
#ifndef linkdlst_h
#include <iostream>
#include <string>
/* HUGELY IMPORTANT NOTE:
*
* This class is dependant upon the other node class! It will fail without it! */
#include "numlist.h"
using namespace std;
class concordance
{
private:
struct node
{
string data;
numlist line_nums;
node *next;
};
node *list_head;
// Methods
bool is_before(string list_data, string data);
bool is_same(string list_data, string data);
bool is_after(string list_data, string data);
//Note: is_first is implied--it's a one line thing
string tolowercase(string str);
public:
concordance();
~concordance();
void append(string data, int n);
void insert(string data, int n);
void print();
};
#define linkdlst_h
#endif
Exert from wordlist.cpp (I didn't include the private functions such as touppercase and is_same--they work.)
concordance::concordance()
{
list_head = NULL;
}
concordance::~concordance()
{ //The destructor may have to do something here.
node *previous;
node *current;
previous = current = list_head;
while (current != NULL) //Delete each item in the list.
{
current = previous -> next;
previous -> line_nums.~numlist();
delete previous;
previous = current;
}
previous = current = list_head = NULL;
}
void concordance::insert(string data, int n)
{
node* current = list_head;
node* previous = list_head;
node* newnode = NULL;
bool done = false; // After the loop has executed, exit it.
// Create a node to insert the data into
newnode = new(node);
newnode -> data = data;
newnode -> line_nums.append(n);
// Build the list by inserting data in an organized manner.
if (list_head != NULL)
{
while (done == false)
{
if (is_before(current -> data, data))
{ //Insert into the list
newnode -> next = previous -> next;
previous -> next= newnode;
done = true;
}
else if (is_same(current -> data, data))
{
// cout << "is_same ";
//Append line number to line number list
newnode -> line_nums.append(n);
done = true;
}
else
{ //if !is_before and !is_same, it must be is_after.
if (current -> next == NULL)
{
//The end of list has been reached.
//Insert at the end
newnode -> next = NULL;
current -> next = newnode;
done = true;
}
else
{
previous = current;
current = current -> next;
done = false;
}
}
}
}
else
{
newnode -> next = NULL;
list_head = newnode;
}
}
void concordance::print()
{
node *current;
current = list_head;
while (current != NULL)
{
cout << current -> data << " <- data | position -> ";
current -> line_nums.print();
cout << endl;
current = current -> next;
}
}
numlist.h
/* Source: Program 0, Assignment 7. */
#ifndef numlist_h
#include <iostream>
using namespace std;
class numlist
{
private:
struct node
{
int data;
node *next;
};
node *list;
public:
typedef node *node_ptr;
numlist();
~numlist();
bool defined;
void append(int n);
void print();
};
#define numlist_h
#endif
numlist.cpp
#include "numlist.h"
numlist::numlist()
{
list = NULL;
}
numlist::~numlist()
{ //The destructor may have to do something here.
node *previous;
node *current;
previous = current = list;
while (current != NULL) //Delete each item in the list.
{
current = previous -> next;
delete previous;
previous = current;
}
previous = current = list = NULL;
}
void numlist::append(int str)
{
node *current;
node *newnode;
current = newnode = NULL;
//Create a new node to put the data in.
newnode = new(node);
newnode -> data = str;
newnode -> next = NULL;
cout << " List Head: " << list << " Current: " << current << endl;
//Decide where to put it.
if (current == NULL) //Then this is an empty list.
{
list = newnode;
}
else //Find the end of the list
{
while (current -> next != NULL)
{
current = current -> next;
}
cout << " List Head: " << list << " Current: " << current << endl;
current -> next = newnode;
}
// print();
}
void numlist::print()
{
node *current;
current = list;
while (current != NULL)
{
cout << current -> data << " ";
current = current -> next;
}
}
My test program for wordlist.cpp simply asks for input (cin) and uses the insert procedure to add data to the list.
The test program for numlist.cpp just adds a bunch of data and prints out the list.
Thanks for any suggestions you have. I'm out of ideas here.
