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const numbers=15;
 
type 
    ptk = ^phonebook;
    phonebook = record
     phn: array [1..numbers] of string[50];
     fio: string[50];
     adr: string[50];
     next: ptk;
    end;
 
Var 
    f: file of phonebook;
    head: ptk;
    
 
Procedure add(var head: ptk);
 var
  newrecord: ptk;
  tmprecord: ptk;
begin 
  new(newrecord);
  readln(f,newrecord);   
  newrecord^.next := nil;  
  if head = nil then 
     head := newrecord
  else
  begin
     tmprecord := head;
     while tmprecord^.next <> nil do 
        tmprecord := tmprecord^.next;
     tmprecord^.next := newrecord;
  end;
end;  
 
   
   
Procedure loading;
Begin 
head:=nil;
Assign(f,'phonesbook.txt');
Reset(f);
While not eof(f) do 
 begin 
  add(head);
  seek(f,filepos+1);
 end;
end;
 
 
Procedure keydown;
var 
 key:char;
begin
  key:=readkey;
    case Key of
  #9: addabn;
  'x': deleteab;
  'l': LIST;
  #27: inc(z);
  'd': changeab;
  's': search;
     end;
end;
  
Procedure print;
Var 
 p: ptk;
Begin 
While p <> nil do 
 with p^ do 
  begin 
   Write(fio,' ',adr,' ',phn);
   Writeln;
  end;
end;
   
Procedure addabn;
Begin 
 Writeln('Adding new abbonent');
 Writeln('Enter name ');
 Readln(phonesbook.fio);
 Writeln('Enter address ');
 Readln(phonesbook.adr);
 Writeln('How many phone numbers you want to enter?');
 Read(o);
 Readln;
 for i:=1 to o do 
  begin
   Writeln('Enter phone number ');
   readln(phonesbook.phn[i]);
  end;
 seek(f,filesize-1);
 Write(phonebook);
end;
 
 
 
 
 
 
 
 Begin
    loading;
   Repeat
 clrscr;
 Writeln('To enter the subscriber press TAB');
 Writeln('To view a list of subscribers, press L');
 Writeln('To change the user data type available user data, after you press d');
 Writeln('To delete the contact, type the full name of the caller, after you press x');
 Writeln('To search for a subscriber, enter any information after you press s');
 Writeln('To exit, press  ESC');
 keydown;
  Until z<>0;
  closefb;
  End.

type 
tfile=file of phonebook;

var f:tfile;

Procedure loading(var f:tfile);