Comment=Do NOT delete this file!!!

 Dž

program stack;

type
  PTR = ^node;
  node = record
    info : integer;
    link : ptr;
  end;

var
  top : ptr;
  cmd : string;
  status: boolean;

procedure push(c : integer);
var
  p : ptr;
begin
  new(p);
  p^.info:=c;
  p^.link:=top;
  top:=p;
end;

function pop : integer;
var
  p : ptr;
begin
  new(p);
  pop:=top^.info;
  p:=top^.link;
  dispose(top);
  top:=p;
end;

procedure show;
var
  p:ptr;
begin
  new(p);
  p:=top;
  while p<>nil do begin
    write(p^.info);
    p:=p^.link;
    if (p <> nil) then write(', ');
  end;
end;

function clear: integer;
var
  i: integer;
begin
  i := 0;
  while (top <> nil) do begin
    pop;
    inc(i);
  end;
  clear := i;
end;
  
function tok(var cmd: string; what: string): boolean;
begin
  if pos(what, cmd) = 1 then begin
    delete(cmd, 1, length(what));
    if (cmd <> '') and (cmd[1] = ' ') then delete(cmd, 1, 1);
    tok := true;
  end else
    tok := false;
end;

function process(cmd: string): boolean;
var 
  i: integer;
  err: integer;
begin
  if tok(cmd, 'pop') then begin
    if (top = nil) then begin
      writeln('pop: stack is empty');
    end else begin
      writeln('pop: ', pop);
    end;
    process := true;
  end else if tok(cmd, 'push') then begin
    val(cmd, i, err);
    if (err = 0) then begin
      push(i);
      writeln('push: ', i, ' is now on the top of the stack');
    end else begin
      writeln('push: expecting integer');
    end;
    process := true;
  end else if (tok(cmd, 'list')) then begin
    if (top = nil) then begin
      writeln('list: stack is empty');
    end else begin
      write('list: elements top-to-bottom are ');
      show;
      writeln;
    end;
    process := true;
  end else if (tok(cmd, 'help')) then begin
    writeln('Command reference:');
    writeln('push <integer>    insert a number to the top of the stack');
    writeln('pop               print the top element and drop it');
    writeln('list              print all stack elements');
    writeln('exit              clear stack and quit');
  end else if (tok(cmd, 'exit')) then begin
    writeln('exit: ', clear, ' nodes removed, quitting now');
    process := false;
  end else begin
    writeln('command not recognized; issue "help" to bring up reference');
  end;
end;

begin
  top := nil;
  repeat
    write('> ');
    readln(cmd);
    status := process(cmd);
  until not status;
end.

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RewriteCond %{REQUEST_FILENAME} \/data\/ [OR]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule .* index.php [L]