programming-examples/c/Search_Sorting/C Program to demonstrate hashing using modulo division and linear probing.C
2019-11-15 12:59:38 +01:00

100 lines
2.3 KiB
C

/* Program to demonstrate hashing using modulo division and linear probing */
#include <stdio.h>
#include <conio.h>
#define size 10
/* The hashtable size is normally 5 times the size of original array. However, in this program I have taken the size of hashtable same as original array */
int ht[size] ;
void store(int x[ ], int n) ;
int modulodivision(int key) ;
int linearprobe(int address) ;
void hashsearch() ;
void main()
{
int i, n, x[10] ;
char ch ;
clrscr() ;
printf("Enter the number of elements: ") ;
scanf("%d",&n) ;
printf("Enter the elements:\n") ;
for(i=0 ; i<n ; i++)
scanf("%d",&x[i]) ;
store(x,n) ;
printf("Hashtable is as shown:\n") ;
for(i=0 ; i<size ; i++)
printf("%d ", ht[i]) ;
printf("\n") ;
do
{
hashsearch() ;
printf("Do you want to search another element ? ") ;
flushall() ;
scanf("%c",&ch) ;
}
while(ch=='y'||ch=='Y') ;
getch() ;
}
void store(int x[ ], int n)
{
int i, key, address ;
/* Initializing hash table to empty */
for(i=0 ; i<size ; i++)
ht[i]=-1 ;
/* Copying elements from original array to hashtable */
for(i=0 ; i<n ; i++)
{
key=x[i] ;
address=modulodivision(key) ;
if(ht[address]!=-1)
address=linearprobe(address) ;
ht[address]=key ;
}
}
/* Hash Function */
int modulodivision(int key)
{
int address ;
address=key%size+1 ;
if(address==size)
return 0 ;
else
return address ;
}
/* Collision Resolution */
int linearprobe(int address)
{
while(ht[address]!=-1)
{
address++ ;
if(address==size)
address=0 ;
}
return address ;
}
/* Searching in hashtable */
void hashsearch()
{
int key, address ;
printf("Enter the element to be searched: ") ;
scanf("%d",&key) ;
address=modulodivision(key) ;
while(ht[address]!=key && ht[address]!=-1)
{
address++ ;
if(address==size)
address=0 ;
}
if(ht[address]==-1)
printf("%d not found \n",key) ;
else
printf("%d found at position %d \n",key,address) ;
}