⟦7d97edbac⟧

E3 Source Code



with Binary_Trees_Pkg, Bounded_String, Text_Io;
use Bounded_String;

package body Set_Of_Links is

    Lower : constant Integer := -1;
    Equal : constant Integer := 0;
    Upper : constant Integer := 1;

-- ----------------------------------------------------
-- Definition des fonctions pour le paquetage generique
-- ----------------------------------------------------

    function Compare (A, B : Link) return Integer is
    begin
        if Image (A.First) = Image (B.First) and
           Image (A.Second) = Image (B.Second) then
            return Equal;
        else
            if Image (A.First) < Image (B.First) then
                return Lower;
            else
                return Upper;
            end if;
        end if;
    end Compare;


    procedure Write (A : Link) is
    begin
        Text_Io.Put_Line ("First ->" & Image (A.First) &
                          " / Second ->" & Image (A.Second) &
                          " / State ->" & Lock'Image (A.State));
    end Write;


    procedure Show is new Links_Tree.Visit (Write);


-- ---------------------------------------
-- Definition des fontions de Set_of_Links
-- ---------------------------------------

    function Make_Link (First_Item, Second_Item : String; Link_State : Lock)
                       return Link is
        Tmp_Link : Link;
    begin
        Bounded_String.Free (Tmp_Link.First);
        Bounded_String.Free (Tmp_Link.Second);
        if First_Item > Second_Item then
            Bounded_String.Copy (Tmp_Link.First, First_Item);
            Bounded_String.Copy (Tmp_Link.Second, Second_Item);
        else
            Bounded_String.Copy (Tmp_Link.First, Second_Item);
            Bounded_String.Copy (Tmp_Link.Second, First_Item);
        end if;
        Tmp_Link.State := Link_State;
        return Tmp_Link;
    end Make_Link;


    procedure Create (Set : in out Object) is
    begin
        Set.Root := Links_Tree.Create;
    end Create;


    procedure Destroy (Set : in out Object) is
    begin
        Links_Tree.Destroy (Set.Root);
    end Destroy;


    procedure Add_New (First_Item, Second_Item : String;
                       Link_State : Lock;
                       Set : in out Object) is
        Tmp_Link : Link;
    begin
        Tmp_Link := Make_Link (First_Item, Second_Item, Link_State);
        Links_Tree.Insert (Tmp_Link, Set.Root);

    exception
        when Links_Tree.Duplicate_Value =>
            raise Duplicate_Value;
    end Add_New;


    procedure Modify_State (First_Item, Second_Item : String;
                            Link_State : Lock;
                            Set : in out Object) is
        Tmp_Link, Result_Link : Link;
        Result : Boolean;
    begin
        Tmp_Link := Make_Link (First_Item, Second_Item, Link_State);
        if Links_Tree.Is_Found (Tmp_Link, Set.Root) then
            Links_Tree.Replace_If_Found
               (Tmp_Link, Set.Root, Result, Result_Link);
        end if;
    end Modify_State;


    procedure Exchange (First_Item, Second_Item, Third_Item : String;
                        Set : in out Object) is
        New_Link, Old_Link, Result_Link : Link;
        Result : Boolean;
        Set_Iter : Links_Tree.Iterator;
    begin
        Old_Link := Make_Link (First_Item, Second_Item, No_State);
        New_Link := Make_Link (First_Item, Third_Item, No_State);
        if Links_Tree.Is_Found (Old_Link, Set.Root) and
           Links_Tree.Is_Found (New_Link, Set.Root) then
            Set_Iter := Links_Tree.Make_Iter (Set.Root);
            while Links_Tree.More (Set_Iter) loop
                Links_Tree.Next (Set_Iter, Result_Link);
                exit when Compare (Result_Link, Old_Link) = Equal;
            end loop;
            if Result_Link.State = Unlinked then
                Old_Link := Make_Link (First_Item, Second_Item, Linked);
                New_Link := Make_Link (First_Item, Third_Item, Unlinked);
            else
                Old_Link := Make_Link (First_Item, Second_Item, Unlinked);
                New_Link := Make_Link (First_Item, Third_Item, Linked);
            end if;
            Links_Tree.Replace_If_Found
               (Old_Link, Set.Root, Result, Result_Link);
            Links_Tree.Replace_If_Found
               (New_Link, Set.Root, Result, Result_Link);
        end if;
    end Exchange;


    function Exist (First_Item, Second_Item : String; Set : Object)
                   return Boolean is
        Tmp_Link : Link;
    begin
        Tmp_Link := Make_Link (First_Item, Second_Item, No_State);
        return Links_Tree.Is_Found (Tmp_Link, Set.Root);
    end Exist;


    procedure List (Item : String; Link_State : Lock; Set : Object) is
        Tmp_Link : Link;
        Set_Iter : Links_Tree.Iterator;
    begin
        Set_Iter := Links_Tree.Make_Iter (Set.Root);
        while Links_Tree.More (Set_Iter) loop
            Links_Tree.Next (Set_Iter, Tmp_Link);
            if (Image (Tmp_Link.First) = Item or
                Image (Tmp_Link.Second) = Item) and
               Tmp_Link.State = Link_State then
                if Image (Tmp_Link.First) = Item then
                    Text_Io.Put_Line (Image (Tmp_Link.Second));
                else
                    Text_Io.Put_Line (Image (Tmp_Link.First));
                end if;
            end if;
        end loop;
    end List;


    function What_State
                (First_Item, Second_Item : String; Set : Object) return Lock is
        Search_Link, Found_Link : Link;
        Set_Iter : Links_Tree.Iterator;
    begin  
        Set_Iter := Links_Tree.Make_Iter (Set.Root);
        Search_Link := Make_Link (First_Item, Second_Item, No_State);
        while Links_Tree.More (Set_Iter) loop
            Links_Tree.Next (Set_Iter, Found_Link);
            if Compare (Found_Link, Search_Link) = Equal then
                return Found_Link.State;
            end if;
        end loop;
        return No_State;
    end What_State;


    procedure Dump (Set : Object) is
    begin
        Show (Set.Root, Links_Tree.Inorder);
    end Dump;


end Set_Of_Links;
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⟦7d97edbac⟧ Ada Source

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