type pt item item record data string 20 next pt end var stack pt integ

type
	pt = ^item;
	item = record
		data : string[20];
		next : pt;
	end;

var
	stack : pt;
	i : integer;
	s : string;

procedure stack_push(var stack : pt; data : string[20]);
var
	x : pt;
begin
	New(x);
	x^.data := data;
	x^.next := stack;
	stack := x;
end;

function stack_pop(var stack : pt) : string[20];
var
	tmp : string[20];
	x : pt;
begin
	tmp := stack^.data;
	x := stack;
	stack := stack^.next;
	Dispose(x);
	stack_pop := tmp;
end;

procedure stack_print(stack : pt);
var
	t : pt;
begin
	t:=stack;
	repeat
		write(t^.data, ' ');
		t:=t^.next;
	until t=nil;
end;

begin
	stack:=nil;
	for i:=1 to 5 do
	begin
		str(i, s);
		stack_push(stack, s);
	end;
	stack_print(stack);
	writeln;
	writeln(stack_pop(stack));
	writeln(stack_pop(stack));
	stack_print(stack);
end.