Help needed! I wrote a implement for hash table, but I have some problems:

1. Please find a way to replace the global value int size and int max.

2. Write a function to print probe value for each insert, and give the average probe value for all insert.

3. I try to input a big txt file to this implement, but the void init_array() always crash when I change max=10 to max=7477, I don't know why.

The implement code:

#include

#include

#define base 128

/* to store a data (consisting of key and value) in hash table array */

struct item

{

char *key;

char *value;

};

/* each hash table item has a flag (status) and data (consisting of key and value) */

struct hashtable_item

{

int flag;

/*

* flag = 0 : data does not exist

* flag = 1 : data exists at given array location

* flag = 2 : data was present at least once

*/

struct item *data;

};

struct hashtable_item *array;

int size = 0;

int max = 10;

/* this function returns corresponding index of the given key */

int hashcode(char *key)

{

return ((key[0]*base^2) % max+(key[1]*base)%max+key[2]%max)%max;

}

/* this function initializes the hash table array */

void init_array()

{

int i;

for (i = 0; i < max; i++)

{

array[i].flag = 0;

array[i].data = NULL;

}

}

/* this function inserts an element in the hash table */

void insert(char *key, char *value)

{

int index = hashcode(key);

int i = index;

int h = 1;

struct item *new_item = (struct item*) malloc(sizeof(struct item));

new_item->key = key;

new_item->value = value;

/* probing through the array until an empty space is found */

while (array[i].flag == 1)

{

if (array[i].data->key == key)

{

/* case when already present key matches the given key */

printf(" This key is already present in hash table, hence updating it's value ");

array[i].data->value = value;

return;

}

i = (i + (h * h)) % max;

h++;

if (i == index)

{

printf(" Hash table is full, cannot add more elements ");

return;

}

}

array[i].flag = 1;

array[i].data = new_item;

printf(" Key (%s) has been inserted ", key);

size++;

}

/* to remove an element form the hash table array */

void remove_element(char *key)

{

int index = hashcode(key);

int i = index;

int h = 1;

/* probing through the hash table until we reach at location where there had not been an element even once */

while (array[i].flag != 0)

{

if (array[i].flag == 1 && array[i].data->key == key)

{

/* case where data exists at the location and its key matches to the given key */

array[i].flag = 2;

array[i].data = NULL;

size--;

printf(" Key (%s) has been removed ", key);

return;

}

i = (i + (h * h)) % max;

h++;

if (i == index)

{

break;

}

}

printf(" Key does not exist ");

}

/* to display the contents of hash table */

void display()

{

int i;

for(i = 0; i < max; i++)

{

if (array[i].flag != 1)

{

printf(" Array[%d] has no elements ", i);

}

else

{

printf(" Array[%d] has elements %s (key) and %d (value) ", i, array[i].data->key, array[i].data->value);

}

}

}

int size_of_hashtable()

{

return size;

}

void main()

{

int choice, n, c;

char key, value;

system("cls");

array = (struct hashtable_item*) malloc(max * sizeof(struct hashtable_item*));

init_array();

do {

printf("Implementation of Hash Table in C with Quadratic Probing. ");

printf("MENU-: 1.Inserting item in the Hash table"

" 2.Removing item from the Hash table"

" 3.Check the size of Hash table"

" 4.Display Hash table"

" Please enter your choice-:");

scanf("%d", &choice);

switch(choice)

{

case 1:

printf("Inserting element in Hash table ");

printf("Enter key and value-:\t");

scanf("%s %[^ ]", &key, &value);

insert(key, value);

break;

case 2:

printf("Deleting in Hash table Enter the key to delete-:");

scanf("%s", &key);

remove_element(key);

break;

case 3:

n = size_of_hashtable();

printf("Size of Hash table is-:%d ", n);

break;

case 4:

display();

break;

default:

printf("Wrong Input ");

}

printf(" Do you want to continue-:(press 1 for yes)\t");

scanf("%d", &c);

}while(c == 1);

getch();

}