im a student of 2nd year BS, doing my BS in Computer Science.
Here I want to include a program by me, may be someone will be helped by me :)
#include<stdio.h>
#include<conio.h>
#include<stdlib.h>
int* createHashTable(void);
void getData(void);
void formatting(void);
int insertData(int);
float chkLoadFactor(int, int);
int collision_LinearProbing(int, int,int);
int generateKey(int);
void rehashing(void);
#define dataSize 15
#define empty -1
#define fail 0
#define success 1
int dataArray[dataSize];
int hashSize = 5;
int* head;
int* cur;
void main(void)
{
int count, status;
int filledSpaces = 0;
float loadFactor = 0;
clrscr();
formatting();
getData();
head = createHashTable();
for( count = 0; count < dataSize ; count++)
{
if(loadFactor > 0.5)
rehashing();
status = insertData(dataArray[count]);
if(status == success)
filledSpaces++;
loadFactor = chkLoadFactor(status, filledSpaces);
if(loadFactor <= 0.5)
printf("LF aftr %d is = %f\t", dataArray[count], loadFactor);
if(status == fail)
printf("\nNo room left for %d\n", dataArray[count]);
}
cur = head;
printf("\n\nHash Table content = [");
for(count = 0; count < hashSize ; count++)
{
printf("%d, ", *cur);
cur++;
}
printf("\b\b]");
getch();
}
int* createHashTable(void)
{
int i;
/********************** Allocating Memory for Hash Table *********************/
head = (int*)malloc(sizeof(hashSize*2));
cur = head;
/********************** Initialize HashTable *********************************/
for( i = 0; i <=hashSize; i++)
{
*cur = empty;
cur++;
}
cur = head;
return(head);
}
void getData(void)
{
int i;
randomize();
printf("\n");
printf("Data[]={");
for(i =0; i < dataSize; i++)
{
dataArray[i] = random(50);
printf("%d,", dataArray[i]);
}
printf("\b}\n\n");
}
void formatting(void)
{
int i;
printf("\n");
for(i =0; i<=79 ; i++)
printf("*");
printf("\n......... Prgogram title\t\t# Hash Table");
printf("\n......... Created by\t\t # Romasa Qasim");
printf("\n......... Description\t\t # Creation of Hash Table, generation of,");
printf("\t\t\t\t\t Key, Insertion, Searching and Deletion");
printf("\t\t\t\t\t of data in the Hash Table\n");
for( i =0; i<=79 ; i++)
printf("*");
}
int insertData(int data)
{
int hashIndex,count = 0;
hashIndex = generateKey(data);
if( *(head+hashIndex) == empty)
{
*(head+hashIndex) = data;
return(success);
}
else
return(collision_LinearProbing((++hashIndex%hashSize), count, data));
}
float chkLoadFactor(int status, int filledSpaces)
{
float loadFactor;
if (status == success)
{
loadFactor = filledSpaces / (float)hashSize;
return(loadFactor);
}
else
return(1);
}
int collision_LinearProbing(int hashIndex, int count, int data)
{
if(count == hashSize)
return(fail);
if (*(head+hashIndex) == empty)
{
*(head+hashIndex) = data;
return(success);
}
else
{
collision_LinearProbing((++hashIndex % hashSize), ++count, data);
}
}
int generateKey(int data)
{
int key;
key = data % hashSize;
return(key);
}
void rehashing(void)
{
int count;
int status;
hashSize = hashSize * 2;
head = (int*)realloc(head, sizeof(hashSize*2));
for( count = 0; count <hashSize; count++)
{
*(head+count) = -1;
}
for(count = 0; count < dataSize; count++)
{
status = insertData(dataArray[count]);
}
}
