kodovi/stek-redopsl/RedOpsl.mod

   1 IMPLEMENTATION MODULE RedOpsl;
   2 FROM Info IMPORT InfoTip;
   3
   4 PROCEDURE MakeNull(VAR q : RedOpslTip);
   5 BEGIN
   6   WITH q DO
   7     Prvi := 0;
   8     Zadnji := 0
   9   END
  10 END MakeNull;
  11
  12 PROCEDURE Empty(VAR q : RedOpslTip) : BOOLEAN;
  13 BEGIN
  14   RETURN q.Zadnji = 0
  15 END Empty;
  16
  17 PROCEDURE First(VAR q : RedOpslTip;
  18                 VAR x : InfoTip;
  19                 VAR ok : BOOLEAN);
  20 BEGIN
  21   IF Empty(q) THEN
  22     ok := FALSE
  23   ELSE
  24     ok := TRUE;
  25     WITH q DO
  26       x := Element[Prvi]
  27     END
  28   END
  29 END First;
  30
  31 PROCEDURE AddOne(i : CARDINAL) : CARDINAL;
  32 BEGIN
  33   IF i = Maxred THEN
  34     RETURN 1
  35   ELSE
  36     RETURN i+1
  37   END
  38 END AddOne;
  39
  40 PROCEDURE PopFirst(VAR q : RedOpslTip;
  41                    VAR ok : BOOLEAN);
  42 BEGIN
  43   IF Empty(q) THEN
  44     ok := FALSE
  45   ELSE
  46     ok := TRUE;
  47     WITH q DO
  48       IF Prvi = Zadnji THEN
  49         MakeNull(q)
  50       ELSE
  51         Prvi := AddOne(Prvi)
  52       END
  53     END
  54   END
  55 END PopFirst;
  56
  57 PROCEDURE AddRear(VAR q : RedOpslTip;
  58                   x : InfoTip;
  59                   VAR ok : BOOLEAN);
  60 BEGIN
  61   WITH q DO
  62     IF AddOne(Zadnji) = Prvi THEN
  63       ok := FALSE
  64     ELSE
  65       ok := TRUE;
  66       IF Empty(q) THEN
  67         Prvi := 1;
  68         Zadnji := 1
  69       ELSE
  70         Zadnji := AddOne(Zadnji)
  71       END;
  72       Element[Zadnji] := x
  73     END
  74   END
  75 END AddRear;
  76
  77 END RedOpsl.