Hash Table Implementation
 

Hi everyone,
Since it's the weekend, I can't get assistance from my professor or his assistant until Monday.
My deadline for submission is approaching and I'd feel a lot safer getting as much work as I can.

I'm implementing a hash table to store strings using linear probing. My implementation results in my program hanging and I would like some insight as to why it's hanging. Any help would be appreciated.

I'm sure the problem lies within my linear probing function and/or the comparison of strings.
Omitting ! produces a result but the desired one.

If you have further questions pm or email at [email removed].

Preview of the HashDef.h
I've included all the files necessary to test any modification you might make.

Thank you in advance for any help as well as for your time.

#ifndef H_HashDef

#define H_HashDef



#include <iostream>

#include <string>

#include <fstream>

#include <cctype>

#include <iomanip>

using namespace std;







class HtType

{

public:

        HtType();

        //default constructor

        //initializes Size, the number 

        //of current elements in the table

        void ReadData();

        int hashFunction(const char *key, int keyLenght);

        void LinearProbing();

        void PrintData();

                

private:

        int size;

        string word[131];

        const char *word2;

        int len;

        int hIndex;

        int HTSIZE;

        string hashTable[131];

        int IndexStatusList[131];

        

};

HtType::HtType()

{

        size = 0;

        HTSIZE = 131;

        for(int b = 0; b < HTSIZE;b++)

        {

                IndexStatusList[b] = 0;

        }

        for(int c = 0; c < HTSIZE; c++)

        {

                hashTable[c] = " ";

        }

}

void HtType::ReadData() 

{

        ifstream DataIn;



        DataIn.open("words.txt");

        if(!DataIn)

        {

                cout <<"Error opening data file\n";

        }

        else

        {

                DataIn >> word[size];

                size++;

                while(!DataIn.eof())

                {

                DataIn >> word[size];

                size++;

                }



                

        }

}

int HtType::hashFunction(const char *key, int keyLenght)

{

        int sum = 0;

        for(int j =0; j < keyLenght ; j++)

        {

                sum = sum + static_cast<int>(tolower(key[j]));

                

        }

        return sum = sum % HTSIZE;

}

void HtType::LinearProbing()

{

        for(int a = 0; a < size; a++)

        {

                len = static_cast<int>(word[a].length());

                word2 = word[a].data();               //copies string as a c-string argument

                hIndex = hashFunction(word2,len);

                //int i = 1;

                if(IndexStatusList[hIndex] == 0)

                {

                        hashTable[hIndex] = word[a];

                        IndexStatusList[hIndex] = 1;

                }

                else

                {

                        int i = 1;

                while(IndexStatusList[hIndex] != 0)

                {

                        if(!word[a].compare(word2))

                        {

                                int addone = IndexStatusList[hIndex];

                                addone++;

                                IndexStatusList[hIndex] = addone;

                        }

                        else

                        {

                        hIndex = (hashFunction(word2,len) + i) % HTSIZE;

                        i++;

                        }

                }

                        hashTable[hIndex] = word[a];

                        IndexStatusList[hIndex] = 1;

                }

                

        }

}

void HtType::PrintData()

{

        for(int a = 0; a < HTSIZE; a++)

        {

                cout << hashTable[a]<< "\n";        

        }

        



}

#endif

Re: Hash Table Implementation
 

1. It seems you don't implement any hash tables. A hash table is a container with insert, find and (may be) erase operations. But I can see only chimerical class - a mix of a fixed data file reading from unknown (for me) source, mysterious linearProbing method and final printing. Do you know that there is a wonderful C++ lexical construct called comment?..
2. Why the attachment is so big (1M) zip? All sources of your project must have a packed size less than 2-3K...
3. Next time use code tag with a language specifier:
[code=cplusplus]
... C++ source codes ...
[/code]

Re: Hash Table Implementation
 

Thanks for the advice. I didn't understand the syntax highlighting.
My program doesn't require me to use any of those functions yet.
I couldn't if I wanted to at this moment.
The linear probing should just look for the next available and empty slot in the array when collision occurs.
My hashfunction assigns a value to hIndex by calculating the ASCII value of the string.

I'm currently trying a different approach i thought of this morning.
Thanks again for your time.