//program to search an integer in an array of N integer using binary search method
#include<iostream.h>
#include<conio.h>
int Binary_Search(int a[],int n,int element);
void main()
{ clrscr();
  int A[20],N,ELEMENT,i,INDEX;
  cout<<"\n Enter the number of elements:";//Ascending order
  cin>>N;
  cout<<"\n Enter the elements of array:";
  for(i=0;i<N;i++)
  { cout<<"\n Enter A["<<i<<"]:";
cin>>A[i];
  }
  cout<<"\n Enter the element to be searched:";
  cin>>ELEMENT;
  INDEX=Binary_Search(A,N,ELEMENT);
  if(INDEX==-1)
  cout<<"\n Unsuccessful search";
  else
  cout<<"\n Element is present at "<<INDEX<<" and  is at position "<<(INDEX+1);
  getch();
}

int Binary_Search(int a[],int n,int element)
{ int beg=0,last=n-1,mid;
  while(beg<=last)
  { mid=(beg+last)/2;
if(a[mid]==element)
return mid;
else
if(a[mid]<element)
beg=mid+1;
else
last=mid-1;
  }
  return(-1);
}

//program to store the details of mobile
#include<fstream.h>
#include<conio.h>
#include<process.h>
#include<stdio.h>
class MOBILE
{ private:
  int ModelNo;
  char Brand[20];
  int Price;
 public:
 int get_modelno()
  { return(ModelNo);
  }
  void enter();
  void show();
};
void MOBILE::enter()
{ cout<<"\n Enter the details";
  cout<<"\n\n Enter the model number:";
  cin>>ModelNo;
  cout<<"\n Enter the brand:";
  gets(Brand);
  cout<<"\n Enter the price:";
  cin>>Price;
}
void MOBILE::show()
{ cout<<"\n Model No.: "<<ModelNo;
  cout<<"\n Brand: "<<Brand;
  cout<<"\n Price: "<<Price;
}
void main()
{ clrscr();
  MOBILE mob;
  char p;
  ofstream ofile;
  ofile.open("MOBILE.DAT",ios::app|ios::binary);
  if(!ofile)
  { cout<<"\n File can not open";
exit(1);
  }
  do
  {
   mob.enter();
   ofile.write((char*)&mob,sizeof(mob));
   cout<<"\n Do you want to continue:";
   cin>>p;
  }while(p=='y'||p=='Y');
  ofile.close();
  ofile.open("TEMP.DAT",ios::out|ios::binary);
  ifstream ifile;
  ifile.open("MOBILE.DAT",ios::in|ios::binary);
  if(!ifile || !ofile)
  { cout<<"\n File can not read";
    exit(1);
  }
  int flag=0,r;
  cout<<"\n Enter the model number you want to delete:";
  cin>>r;
  while(ifile.read((char*)&mob,sizeof(mob)))
  { if(mob.get_modelno()==r)
    { flag=1;
    }
    else
     ofile.write((char *)&mob,sizeof(mob));
  }

if(flag==0)
cout<<"\n Unsuccessful search";
ofile.close();
ifile.close();
remove("MOBILE.DAT");
rename("TEMP.DAT","MOBILE.DAT");
ifile.open("MOBILE.DAT",ios::in|ios::binary);
cout<<"\n Records After Deletion: ";
  while(ifile.read((char*)&mob,sizeof(mob)))
  { mob.show();
    getch();
  }
 ifile.close();
 getch();
}

//program to enter the details of books
#include<iostream.h>
#include<conio.h>
#include<process.h>
#include<fstream.h>
#include<stdio.h>

struct BOOK
{ int BookNo;
  char BookTitle[20];
  int Price;
  int Edition;
}obj;
void main()
{ clrscr();
  int no;
  char p;

  ofstream ofile;
  ofile.open("BOOKS.DAT",ios::app|ios::binary) ;
  if(!ofile)
  { cout<<"\n File can not open";
exit(1);
  }

  do
  { cout<<"\n Enter the book no:";
cin>>obj.BookNo;
cout<<"\n Enter the book title:";
gets(obj.BookTitle);
cout<<"\n Enter the price of book:";
cin>>obj.Price;
cout<<"\n Enter the Edition:";
cin>>obj.Edition;
ofile.write((char*)&obj,sizeof(obj));
cout<<"\n Do you want to continue:";
cin>>p;
  }while(p=='y'||p=='Y');
  ofile.close();
  ifstream ifile;
  ifile.open("BOOKS.DAT",ios::in|ios::binary);
  if(!ifile)
  { cout<<"\n File can not read";
exit(1);
  }
  int flag=0;
  cout<<"\n Enter the book number whose details you want to search:";
  cin>>no;

  while(ifile.read((char *)&obj,sizeof(obj)))
  { if(obj.BookNo==no)
       {flag=1;
cout<<"\n  the book no:"<<obj.BookNo;
cout<<"\n  the book title:"<<obj.BookTitle;
cout<<"\n the price of book:"<<obj.Price;
cout<<"\n  the number of copies:"<<obj.Edition;
break;
      }
  }
  if(flag==0)
cout<<"Record not found";

  ifile.close();
  getch();
}