C++ Programming Code Examples
C++ > Data Structures Code Examples
C++ Program to Implement Hash Tables Chaining with Binary Trees
/* C++ Program to Implement Hash Tables Chaining with Binary Trees */
#include <iostream>
#include <string>
#include <vector>
#include <cstdlib>
using namespace std;
/* Node Class Declaration */
template <class T>
class BSTNode
{
private:
T value;
BSTNode *left, *right;
public:
BSTNode(T value)
{
this->value = value;
left = NULL;
right = NULL;
}
/* Adding element to a node */
void add(T& value)
{
if (value < this->value)
{
if (left)
left->add(value);
else
left = new BSTNode(value);
}
else if (this->value < value)
{
if (right)
right->add(value);
else
right = new BSTNode(value);
}
}
/* Check if node contains element */
bool contains(T& value)
{
if (value < this->value)
{
if (left)
return left->contains(value);
else
return false;
}
else if (this->value < value)
{
if (right)
return right->contains(value);
else
return false;
}
else
{
return true;
}
}
friend class BSTHashtable;
};
/* Table Class Declaration */
class BSTHashtable
{
private:
int size;
vector<BSTNode<string>*>* bucket;
int hash(string& s)
{
unsigned int hashVal = 0;
for (unsigned int i = 0; i < s.length(); i++)
hashVal ^= (hashVal << 5) + (hashVal >> 2) + s[i];
return hashVal % size;
}
public:
BSTHashtable(int vectorSize)
{
size = vectorSize;
bucket = new vector<BSTNode<string>*>(size);
}
/* Adding string in the table */
void add(string& s)
{
int index = hash(s);
if (bucket->at(index) == NULL)
bucket->at(index) = new BSTNode<string>(s);
else
bucket->at(index)->add(s);
}
/* Check if table contains string */
bool contains(string& s)
{
int index = hash(s);
if (bucket->at(index) == NULL)
return false;
cout<<"String \""<<s<<"\" found at index: "<<index<<endl;
return bucket->at(index)->contains(s);
}
/* Display Table */
void display()
{
for (unsigned int i = 0; i < bucket->size(); i++)
{
cout <<"[" << i << "] ";
if (bucket->at(i) != NULL)
{
BSTNode<string> *node = bucket->at(i);
display_bst(node);
}
cout << endl;
}
}
/* Display BST */
void display_bst(BSTNode<string> *node)
{
if (node!=NULL)
{
display_bst(node->left);
cout << node->value << " ";
display_bst(node->right);
}
}
};
/* Main Contains Menu */
int main()
{
BSTHashtable table(10);
string str;
int choice;
while (1)
{
cout<<"\n----------------------"<<endl;
cout<<"Operations on BST Hash Table"<<endl;
cout<<"\n----------------------"<<endl;
cout<<"1.Insert element into the table"<<endl;
cout<<"2.Find element in the table"<<endl;
cout<<"3.Display Table Chained with Binary Tree"<<endl;
cout<<"4.Exit"<<endl;
cout<<"Enter your choice: ";
cin>>choice;
switch(choice)
{
case 1:
cout<<"Enter String to be inserted: ";
cin>>str;
table.add(str);
break;
case 2:
cout<<"Enter String to search: ";
cin>>str;
if (table.contains(str) == 0)
{
cout<<"String \""<<str<<"\" not found in the table"<<endl;
continue;
}
break;
case 3:
cout<<"Displaying Table Chained with Binary Tree: "<<endl;
table.display();
break;
case 4:
exit(1);
default:
cout<<"\nEnter correct option\n";
}
}
return 0;
}
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