#include
#include
using namespace std;
class node
{
public:
string key;
int value;
node * next;
node(string k, int v)
{
key = k;
value = v;
next = NULL;
}
};
class hashTable
{
node** ptrArray;
int cs, ts=7;
public:
hashTable(int ds=7)
{
ptrArray = new node*[ds];
for(int i=0;i<ds;i++)
{
ptrArray[i] = NULL;
}
}
int hashFn(string key)
{
int l = key.length();
int ans =0, p=1;
for(int i=0;i<l;i++)
{
ans += key[l-i-1]*p;
p *= 37;
p %= ts;/// to prevent overflow of no
ans %= ts; /// to limit the indexes within the table size
}
return ans;
}
void insertNode(string key, int value)
{
int index = hashFn(key);
node* n = new node(key,value);
n->next = ptrArray[index];
ptrArray[index] = n;
}
void print()
{
node* temp;
for(int i=0;i<ts;i++)
{
temp = ptrArray[i];
while(temp!=NULL)
{
cout<<temp->key<<" , ";
temp = temp->next;
}
cout<<endl;
}
}
node* searchKey(string key)
{
int idx = hashFn(key);
node* temp = ptrArray[idx];
while(temp!=NULL )
{
if(temp->key==key)
{
return temp;
}
temp = temp->next;
}
return NULL;
}
///complete it ?????
void deleteNode(string key)
{
int idx = hashFn(key);
node* temp = ptrArray[idx];
///deletion at head
if(temp->key == key)
{
ptrArray[idx] = temp->next;
temp->next = NULL;
delete temp;
}
///deletion in middle
node* prev = temp;
while(temp!=NULL)
{
if(temp->key == key)
{
prev->next = temp->next;
temp->next = NULL;
delete temp;
}
///deletion at end
if(temp->next==NULL && temp->key == key)
{
prev->next = NULL;
delete temp;
}
prev = temp;
temp = temp->next;
}
}
};
int main()
{
hashTable h(57);
h.insertNode(“apple”,10);
h.insertNode(“mango”,20);
h.insertNode(“banana”,30);
h.insertNode(“grapes”,40);
h.insertNode(“litchi”,50);
h.insertNode(“strawberry”,60);
h.insertNode(“pear”,10);
h.insertNode(“cherry”,20);
h.insertNode(“guava”,30);
h.insertNode(“orange”,40);
h.insertNode(“kiwi”,50);
h.insertNode(“papaya”,60);
h.print();
string input;
cout<<"Enter the key to delete :"<<endl;
cin>>input;
h.deleteNode(input);
h.print();
return 0;
}
My deletion of node is working for all the nodes present
it’s deleting correctly
but How to handle the case if the given key for deletion is not present and temp becomes NULL at the end