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Problem with closed hashTable,segmentation fault core dumped,problem with insertion

Hash table problem Hey,i am facing a problem with a closed hashtable i am trying to implement... Everything should work correct ,but i get again and again segmentation fault... I am reading words from a file,and insert them in a HashTable object.. There is no remove() function,and i dont used at main.cpp Search() fucntion .. I think there is something wrong with the resize of the hashtable.


What I have tried:

C++
#include <iostream>
#include <fstream>
#include <cstring>
#include "HashTable.h"

using namespace std;

int main()
{
   string filename;
   cout<<"Enter filename: ";
   cin>>filename;
   string w;
   int i,j;
   HashTable s5;

   ifstream ifs;
   ifs.open(filename);
   if(ifs.is_open())
   {
        cout<<"File open ok"<<endl;
        while(ifs>>w)
        {
             for (i = 0;i<w.size();i++)
             {
                unsigned char c=w[i];
                if(isupper(c))
                    w[i]=tolower(c);
             }
            i=0;
            while (i<w.size())
            {
                   if (ispunct((unsigned char)w[i]))
                   {
                       w.erase(i,1);
                   }
                  else
                    {
                        i++;
                    }
            }

            s5.Insert(w,1);
    }
   }
    else
    {
        cout<<"File error"<<endl;
        return 1;
    }
    s5.print();
    ifs.close();
    bool f;
    return 1;
    
}


#ifndef HASHTABLE_H
#define HASHTABLE_H

#include <string>
#include <iostream>

using namespace std;

class word
{
    public:
        string w;
        int freq;
        word(string w,int freq)
        {
            this->w=w;
            this->freq=freq;
        }
};

class HashTable
{
    private:
        int size;
        int elements;
        word  **A;
        unsigned int hash(string);
        unsigned int hash2(unsigned int);
        word *Search(string);
    public:
        HashTable();
        ~HashTable();
        bool Insert(string,int);
        bool Search(string,int);
        void print()
        {
          for(int i=0;i<=size-1;i++)
            if(A[i]!=nullptr)
               cout<<A[i]->w<<" "<<A[i]->freq<<endl;
        }
};

#endif



#include "HashTable.h"
#include <iostream>
#include <cstring>

using namespace std;

HashTable::HashTable()
{
    size=1000;
    elements=0;
    A=new word *[size];
    for(int i=0;i<size;i++)
        A[i]=nullptr;
}

HashTable::~HashTable()
{
    delete[]A;
    A=nullptr;
    elements=0;
    size=0;
}

unsigned int HashTable::hash(string s)
{
    unsigned int h=7;
    for(int i=0;i<=s.length()-1;i++)
       h=h*31+s[i];
    return h%size;
}

unsigned int HashTable::hash2(unsigned int d)
{
    return (d+1)%size;
}

bool HashTable::Insert(string s,int d)
{
    if(Search(s)!=nullptr)
        return false;
    if(elements>=size/2)
    {
        word **temp;
        size*=2;
        temp=new word*[size];
        for(int i=0;i<size;i++)
            temp[i]=nullptr;

        for(int i=0;i<size/2;i++)
        {
            if(A[i]!=nullptr)
            {
                unsigned int p=hash(A[i]->w);
                while(temp[p]!=nullptr)
                    p=hash2(p);
                temp[p]=A[i];
                A[i]=nullptr;
            }        
        }
        delete[]A;
        A=temp;
    }
    unsigned int p=hash(s);
    while(A[p]!=nullptr)
        p=hash2(p);
    A[p]=new  word(s,d);
    elements++;
    return true;
}

word *HashTable::Search(string s)
{
    unsigned int p=hash(s);
    while((A[p]!=nullptr && A[p]->w!=s))
        p=hash2(p);
    return A[p];
}

bool HashTable::Search(string s,int d)
{
    word *p=Search(s);

    if(p==nullptr)
        return false;

    d=p->freq;

    return true;
}
Posted
Updated 5-Jun-21 21:45pm
v3
Comments
Richard Deeming 7-Jun-21 12:20pm    
Removing the content of your question after others have taken the time to answer it is extremely rude.

I have rolled back your destructive edit.

Compiling does not mean your code is right! :laugh:
Think of the development process as writing an email: compiling successfully means that you wrote the email in the right language - English, rather than German for example - not that the email contained the message you wanted to send.

So now you enter the second stage of development (in reality it's the fourth or fifth, but you'll come to the earlier stages later): Testing and Debugging.

Start by looking at what it does do, and how that differs from what you wanted. This is important, because it give you information as to why it's doing it. For example, if a program is intended to let the user enter a number and it doubles it and prints the answer, then if the input / output was like this:
Input   Expected output    Actual output
  1            2                 1
  2            4                 4
  3            6                 9
  4            8                16
Then it's fairly obvious that the problem is with the bit which doubles it - it's not adding itself to itself, or multiplying it by 2, it's multiplying it by itself and returning the square of the input.
So with that, you can look at the code and it's obvious that it's somewhere here:
C#
int Double(int value)
   {
   return value * value;
   }

Once you have an idea what might be going wrong, start using the debugger to find out why. Put a breakpoint on the first line of the method, and run your app. When it reaches the breakpoint, the debugger will stop, and hand control over to you. You can now run your code line-by-line (called "single stepping") and look at (or even change) variable contents as necessary (heck, you can even change the code and try again if you need to).
Think about what each line in the code should do before you execute it, and compare that to what it actually did when you use the "Step over" button to execute each line in turn. Did it do what you expect? If so, move on to the next line.
If not, why not? How does it differ?
Hopefully, that should help you locate which part of that code has a problem, and what the problem is.
This is a skill, and it's one which is well worth developing as it helps you in the real world as well as in development. And like all skills, it only improves by use!
 
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A segmentation fault means that you're using a bad pointer, so you need to run your code with a debugger. It's very unlikely that you will find anyone on this site to inspect your code, looking for the bug, or actually debug it for you. Maybe you've written small programs where you could find a bug by executing the code manually. But that's a very slow way to do it, and once you're working on more complex programs, the fastest way to find problems is with a debugger.
 
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