Problem with doubly linked lists

[drake2212]

So this is my first time on here asking for help but I do visit this forum every now and again when I am taking a programming class. I am trying to get my doubly linked list to work correctly. Also I am having issues with parsing an input file. The function for the parsing is checkInputWord, and I wanted to see if you guys could see what I was messing up. Then in the insertWord function I am trying to either add a node to an empty array of pointers or one that already has some pointers. Here is my code and hopefully it is written well enough so you can understand what I am trying to do.

# include <iostream>
# include <iomanip>
# include <fstream>
# include <string>
# include <cctype>
# include <cstddef>

using namespace std;

const string WORD_FILE = "listing.txt";
const int MAX_SIZE = 26;


struct wordList {
       string newWord;
       wordList *previous;
       wordList *next;
       };

void programIntro();
void checkTextFile (ifstream& wordIn);
void initializeArray (wordList *wordArray[], int &index);
void readTextFile (ifstream& wordIn, wordList* wordArray [], int &index, int arrayCount, string &word1);
void checkInputWord (ifstream &wordIn, wordList* wordArray [], string &word1);
void insertWord (wordList *wordArray [], int &index, string &word1);

int main () {
    
    wordList* theWord[MAX_SIZE];
    int arrayCount = 0;
    int indexes = 0;
    int count;
    string words;
    
    ifstream wordIn;

    
    
    programIntro();
    checkTextFile (wordIn);
    initializeArray(theWord, indexes);
    readTextFile (wordIn, theWord, indexes, arrayCount, words); 
    
    
    system ("pause");
    return 0;
}

void programIntro ()

{
     cout << "**************************************************************************" <<endl;
     cout << "This program will search a text file and place the words in the text file" << endl;
     cout << "into a doubly linked list." << endl << endl;
     cout << "**************************************************************************" << endl;
     
     return;
     
     }

void checkTextFile (ifstream& wordIn) 

{
     
     wordIn.open (WORD_FILE.c_str());
     
     if (!wordIn) 
        cout << "Error! Text File did not open!" << endl;
        
     else
         cout << "File opened correctly!" << endl;
         
     return;
}



void initializeArray (wordList *wordArray[], int &index)

{
     
     for (index = 0; index < MAX_SIZE; index++) {
         wordArray[index] = NULL;
         }
     
     return;
}

void readTextFile (ifstream& wordIn, wordList* wordArray [], int &index, int arrayCount, string &word1)

{
     
     char character;
     char letter;
     arrayCount = 0;
     string word;
     
     wordIn >> word1;
     cout << " READ WORD: " << word1 << endl;
     cout << " ARRAY count = " << arrayCount << endl;
     character = word1[0];
     letter = toupper(character);
     index = letter - 'A';
        
     cout << " Index for Word: " << index << endl << endl;
     checkInputWord (wordIn, wordArray, word1);
     insertWord (wordArray, index, word1);
     
     while (wordIn.eof() != true) {
           
           arrayCount++;
           wordIn >> word1;
           checkInputWord (wordIn, wordArray, word1);
           character = word1[0];
           letter = toupper(character);
           index = letter - 'A';
           cout << " READ WORD: " << word1 << endl;
           cout << " ARRAY count = " << arrayCount << endl;
           
           
           cout << " Index for Word: " << index << endl << endl;
          insertWord (wordArray, index, word1);
     
           }
     
     return;
}
 
void checkInputWord (ifstream &wordIn, wordList *wordArray [], string &word1)

{
     int curr_position = 0;
     int next_position;
     string badWord;
     
          next_position = word1.find_first_of(",.;:)(*&^%$#@!1234567890", curr_position);
          badWord = word1.substr(curr_position, next_position - curr_position);
          
          cout <<  " Current position: " << curr_position << endl << endl;
          cout << " Next position: " << next_position << endl ;
          cout << " Bad Word: " << badWord << endl ;
          
          if (next_position != string::npos) {
             curr_position = next_position + 1;
             next_position = word1.find_first_of(" ,.;:)(*&^%$#@!1234567890", curr_position);
             badWord = word1.substr(curr_position, next_position - curr_position);
             
             cout << " Current position: " << curr_position << endl << endl;
             cout << " Next position: " << next_position << endl << endl;
             cout << " Bad Word: " << badWord << endl << endl;
             } 
     return;
     
     }    
     
void insertWord (wordList *wordArray [], int &index, string &word1)

{
     wordList *theList;
     
           if (wordArray[index] == NULL) {
              theList = new wordList;
              theList->newWord = word1;
              theList->next = NULL;
              theList->previous = NULL;
              wordArray[index] = theList;
              cout << wordArray[index]->newWord << endl;
              }
              
           else {
              wordList *newNode = new wordList;
              newNode->newWord = word1;
              newNode->previous = NULL;
              newNode->next = wordArray[index];
              wordArray[index]->previous = newNode;
              wordArray[index]->next = wordArray[index]->previous;
              
              cout << wordArray[index]->previous->newWord << endl;
              cout << wordArray[index]->next->newWord<< endl;
          }
     
     
     return;
}

[Agni]

I don't really understand what you are doing. You just have an array of structures of type wordList. So basically you are not using the linked list at all !!! You create a node and insert it into the array. I don't think that's how you would be expected to use linked lists. You can use the list itself as a data-structure. Keep the start of the list with you and traverse it as per your needs.

[kvprajapati]

Welcome drake2212,
Please post listing.txt file's content.
I have a suggestion, modify else block of insertWord.

wordList *newNode = new wordList;
              newNode->newWord = word1;
              newNode->previous = NULL;
              newNode->next=NULL;

              theList = wordArray[index];
              while(theList->next!=NULL)
              {
                  theList=theList->next;
              }
              theList->next=newNode;
              theList->next->previous=theList;

[jencas]

The wordList pointer in insertWord() goes out of scope (and therefore is lost) when insertWord returns to the calling function.

[drake2212]

The wordList pointer in insertWord() goes out of scope (and therefore is lost) when insertWord returns to the calling function.

Do you have any suggestions on how to fix this?

[drake2212]

Welcome drake2212,
Please post listing.txt file's content.
I have a suggestion, modify else block of insertWord.

wordList *newNode = new wordList;
              newNode->newWord = word1;
              newNode->previous = NULL;
              newNode->next=NULL;

              theList = wordArray[index];
              while(theList->next!=NULL)
              {
                  theList=theList->next;
              }
              theList->next=newNode;
              theList->next->previous=theList;

Here is what is in the text file.

I like this class. It is much of a challenge. I can't wait to get
some help on this program cuz it is tough!

I tred implementing your suggestion and when I try to output certain indexes I get runtime errors ... any suggestions?