Operatii stiva: creare, parcurgere, adaugare, eliminare

>Operatii in stiva statica:creare, parcurgere, adaugare, eliminare.

program stiv;
type stiva=array[0..100] of integer;
var s:stiva;
    vf,n,i:integer;
    st_plina,st_vida:boolean;
procedure initializare;
var i:integer;
begin
     write('numarul de elemente al stivei=');readln(n);
     for i:=1 to n do s[i]:=0;
     vf:=0;
end;
procedure adaugare;
var e:integer;
begin
     write('elementul care se adauga=');
     readln(e);
     if vf=n then st_plina:=true
             else st_plina:=false;
     if st_plina then
                     begin
                          writeln('depasire stiva');
                          readln;
                     end
                 else
                     begin
                          vf:=vf+1;
                          s[vf]:=e;
                     end;
end;
procedure parcurg;
var i:integer;
begin
     writeln('stiva este:');
     i:=vf;
     while i<>0 do
           begin
                writeln(s[i]:5);
                dec(i);
           end;
     readln;
end;
procedure eliminare;
var e:integer;
begin
     if vf=0 then st_vida:=true
             else st_vida:=false;
     if st_vida then
                    begin
                         writeln('stiva vida');
                         readln;
                    end
                else
                    begin
                         e:=s[vf];
                         dec(vf);
                    end;
     writeln('s-a eliminat elementul ',e);
end;
BEGIN
     initializare;
     for i:=1 to n do  adaugare;
     parcurg;
END.
{PascalZone.uv.ro}