kodovi/stek-redopsl/Stek.mod

   1 IMPLEMENTATION MODULE Stek;
   2 FROM Info IMPORT InfoTip;
   3
   4 PROCEDURE MakeNull(VAR s : StekTip);
   5 BEGIN
   6   s.Top := 0
   7 END MakeNull;
   8
   9 PROCEDURE Empty(VAR s : StekTip) : BOOLEAN;
  10 BEGIN
  11   RETURN s.Top = 0
  12 END Empty;
  13
  14 PROCEDURE Top(VAR s : StekTip;
  15               VAR x : InfoTip;
  16               VAR ok : BOOLEAN);
  17 BEGIN
  18   IF Empty(s) THEN
  19     ok := FALSE
  20   ELSE
  21     ok := TRUE;
  22     WITH s DO
  23       x := Element[Top]
  24     END
  25   END
  26 END Top;
  27
  28 PROCEDURE Pop(VAR s : StekTip;
  29               VAR ok : BOOLEAN);
  30 BEGIN
  31   IF Empty(s) THEN
  32     ok := FALSE
  33   ELSE
  34     ok := TRUE;
  35     DEC(s.Top)
  36   END
  37 END Pop;
  38
  39 PROCEDURE Push(VAR s : StekTip;
  40                x : InfoTip;
  41                VAR ok : BOOLEAN);
  42 BEGIN
  43   WITH s DO
  44     IF Top = Maxstek THEN
  45       ok := FALSE
  46     ELSE
  47       ok := TRUE;
  48       INC(Top);
  49       Element[Top] := x
  50     END
  51   END
  52 END Push;
  53
  54 END Stek.