Algorithm of Hashing Using c/c++

Source code of Hashing using c++ is listed below.
/*
IDE : Codeblocks 10.05
file name : hashing.cpp
*/

#include<iostream>
using namespace std;
class hashing
{
 private:
int hashpos;
int array[50];
 public:
hashing()
{


for(int i=0;i<50;i++)
  array[i]='*';
}
int hashfunction(int );
void askdata();
int linearprobing(int);
int quadraticprobing(int);
void askdeletion();
void deletion(int);
void display();


 };
void hashing::display()
{
 for(int i=0;i<7;i++)
 cout<<"array["<<i<<"]:"<<array[i]<<endl;
}


void hashing::askdata()
 {
  int data;
  cout<<"Enter the data:";
  cin>>data;
  hashpos=hashfunction(data);
  if(array[hashpos]!='*')
// hashpos=linearprobing(hashpos);  
//use linear or quadratic as choice
   hashpos=quadraticprobing(hashpos);
  array[hashpos]=data;
  cout<<endl<<"Data kept at position:"<<hashpos;
 }
//........................................................
int hashing::hashfunction(int data)
 {
  hashpos=data%7;
  return(hashpos);
 }
//................................................
int hashing::linearprobing(int pos)
 {
  while(array[pos++]!='*')
  {
     if(pos==7)
     pos=0;
  }
  return(pos);
 }
//.....................................................
int hashing::quadraticprobing(int pos)
 {
  int i=0;
  int a=pos+i;
  while(array[a]!='*')
  {
 i++;
     a=pos+i*i;
     a%=7;
  }
  return(a);
 }
//.....................................................
void hashing::askdeletion()
{
  int data;
  cout<<"Enter the no. to be deleted:";
  cin>>data;
  deletion(data);
}


void hashing::deletion(int data)
{
 int flag=1,i=1;
 int hashposition=hashfunction(data);
 int a=hashposition;
while((a==hashfunction(array[hashposition])) || (a == (array[hashposition]=='*')))
 {
if(array[hashposition]==data)
    {
     cout<<"Data found and deleted."<<endl;
     array[hashposition]='*';
     flag=0;
     break;
    }
if(array[hashposition]!=data)
 {
  hashposition=a+i*i;
     hashposition%=7;
    i++;
 }
}
 if(flag==1)
   cout<<"Data not found";
}


int main()
{
 hashing obj;
 int choice=1;
 while(choice!=4)
{
 cout<<"\nEnter ur choice:\n"
 <<"1.Insertion\n"
     <<"2.Deletion\n"
     <<"3.Display\n"
     <<"4.Exit\t";
 cin>>choice;
 switch(choice)
 {
  case 1:obj.askdata();
break;
  case 2:obj.askdeletion();
break;
  case 3:obj.display();
 }
}
return 0;
}

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