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;
}

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.

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;

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

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?

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?

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