Hi, how can i avoid of key beeing inserted into wrong location.If i do lets say 3 numbers ,5 digits long like 12345,23445,56745 and choose location 45,they will be inserted to location 45,but if try to insert 67452 to the same location it will be inserted,but i need it to be inserted into its own free location like 52,not 45.And is where any way to detect the location automatically,after inserting number?
#include "stdafx.h"
using namespace std;
const int TABLE_SIZE = 128;
/*
* HashNode Class Declaration
*/
class HashNode
{
public:
int key;
int value;
HashNode* next;
HashNode(int key, int value)
{
this->key = key;
this->value = value;
this->next = NULL;
}
};
/*
* HashMap Class Declaration
*/
class HashMap
{
private:
HashNode** htable;
public:
HashMap()
{
htable = new HashNode*[TABLE_SIZE];
for (int i = 0; i < TABLE_SIZE; i++)
htable[i] = NULL;
}
~HashMap()
{
for (int i = 0; i < TABLE_SIZE; ++i)
{
HashNode* entry = htable[i];
while (entry != NULL)
{
HashNode* prev = entry;
entry = entry->next;
delete prev;
}
}
delete[] htable;
}
/*
* Hash Function
*/
int HashFunc(int key)
{
return key % TABLE_SIZE;
}
/*
* Insert Element at a key
*/
void Insert(int key, int value)
{
int hash_val = HashFunc(key);
HashNode* prev = NULL;
HashNode* entry = htable[hash_val];
while (entry != NULL)
{
prev = entry;
entry = entry->next;
}
if (entry == NULL)
{
entry = new HashNode(key, value);
if (prev == NULL)
{
htable[hash_val] = entry;
}
else
{
prev->next = entry;
}
}
else
{
entry->value = value;
}
}
/*
* Remove Element at a key
*/
void Remove(int key)
{
int hash_val = HashFunc(key);
HashNode* entry = htable[hash_val];
HashNode* prev = NULL;
if (entry == NULL || entry->key != key)
{
cout<<"No Element found at key "<<key<<endl;
return;
}
while (entry->next != NULL)
{
prev = entry;
entry = entry->next;
}
if (prev != NULL)
{
prev->next = entry->next;
}
delete entry;
cout<<"Element Deleted"<<endl;
}
/*
* Search Element at a key
*/
int Search(int key)
{
bool flag = false;
int hash_val = HashFunc(key);
HashNode* entry = htable[hash_val];
while (entry != NULL)
{
if (entry->key == key)
{
cout<<entry->value<<" ";
flag = true;
}
entry = entry->next;
}
if (!flag)
return -1;
}
};
/*
* Main Contains Menu
*/
int main()
{
HashMap hash;
int key, value;
int choice;
while (1)
{
cout<<"\n----------------------"<<endl;
cout<<"Operations on Hash Table"<<endl;
cout<<"\n----------------------"<<endl;
cout<<"1.Insert element into the table"<<endl;
cout<<"2.Search element from the key"<<endl;
cout<<"3.Delete element at a key"<<endl;
cout<<"4.Exit"<<endl;
cout<<"Enter your choice: ";
cin>>choice;
switch(choice)
{
case 1:
cout<<"Enter element to be inserted: ";
cin>>value;
cout<<"Enter key at which element to be inserted: ";
cin>>key;
hash.Insert(key, value);
break;
case 2:
cout<<"Enter key of the element to be searched: ";
cin>>key;
cout<<"Element at key "<<key<<" : ";
if (hash.Search(key) == -1)
{
cout<<"No element found at key "<<key<<endl;
continue;
}
break;
case 3:
cout<<"Enter key of the element to be deleted: ";
cin>>key;
hash.Remove(key);
break;
case 4:
exit(1);
default:
cout<<"\nEnter correct option\n";
}
}
return 0;
}