H. I need to program a queue in ADA, dont know if queue is the real word in English, but you will understand FIFO stack I think ;-) I dont know who to delete an element from the FIFO stack. I have implemented it under pointers, and the thing is like this: .ADS Stack Specification: type NodoCola; type Puntero is access NodoCola; type NodoCola is record Elemento: Tipo_Elemento; Next: Puntero; end record; type Cola is record Registro: Puntero; NumElem: Natural := 0; end record; Deleting the element in out position: procedure Extraer (C: in out Cola) is Aux: Puntero := new NodoCola; begin Aux := C.Registro; if (Es_Vac�a(C)) then raise E_Cola_Vac�a; else C.Registro := C.Registro.Next; C.NumElem := C.NumElem - 1; end if; end Extraer; Thank you for helping me with this ;-) See ya. P.D. If anyone of you could help me, please could you answer into my mailbox :? Thanks anyway ;-) [|] Miguel Angel P�rez (S|r |ceman). [|] Administrador General de Networking Center(R), 2000 [|] Email: iceman@webshack-cafe.com iceman@networking-center.org admin@networking-center.org [|] Networking Center(R) - Proyecto C.I.R.I.T. [|] Web: http://www.networking-center.org [|] FTP: ftp://ftp.networking-center.org [|] IRC: IRC Hispano, [irc.irc-hispano.org], Canal: #Networking.