2Bytesprog2 course_2014_c7_double_lists
21
Prog_2 course- 2014 2 bytes team Kinan keshkeh IT Engineering-Damascus University 3 rd year
Transcript of 2Bytesprog2 course_2014_c7_double_lists
Prog_2 course- 2014
2 bytes team
Kinan keshkeh
IT Engineering-Damascus University
3rd year
Double Lists
Data
next
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v
L_S
Data
next
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Data
pre
v
pre
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next
next
Data
L_E
Definition
Type
D_P = ^D_R;
D_R = Record
ID:integer;
next:D_P;
prev:D_P;
end;
var
L_S, L_E : D_P;
Double Lists Procedures:
1) Insert a Node
2) Delete a Node
3) Search Node
Insert a Node
Data
next
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v
Data
next
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v
Data
next
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v
Data
next
pre
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L_E
Data
next
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L_S
Temp
1)
L_S
Nil 15
next
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Temp L_E
3
next
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v
20
next
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15
next
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v
2)
L_S
S
L_E Temp
3
next
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20
nex
t
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15
next
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3)
L_S
S
L_E
2
next
pre
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Temp
3 n
ext
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20
nex
t
pre
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15
next
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L_S
S
L_E
2
next
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Nil
4)
Temp
procedure D_L_Insert ( var L_S, L_E: D_P; KEY:integer);
var
Temp , S : D_P;
Located: Boolean;
begin
new(Temp);
temp^.ID:=KEY;
temp^.next:=nil;
temp^.prev:=nil; 15
next
pre
v
Temp
If L_S=nil then begin
L_S:=Temp;
L_E:=Temp;
end
Else
begin
S:=L_S;
Located:=False;
while (S<>nil) and (not Located) do if S^.id < key then
S:=S^.next
else
Located:=True;
Temp^.next:=S; +2
points
If S=L_S then
begin
L_S^.prev:=Temp;
L_S:=Temp;
end
Else if S=nil then
begin
Temp^.prev := L_E;
L_E^.next := Temp;
L_E:=Temp;
end
Else
begin
Temp^.prev := S^.prev;
S^.prev^.next := Temp;
S^.prev := Temp;
end;
end;
end; {procedure}
1)
L_S
Nil
Delete a Node
flag
3
L_E
3
next
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v
20
next
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15
next
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L_S L_E
key 3 2)
temp
3 next
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L_S
Nil
temp
L_E
flag
2
3 n
ext
pre
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20
next
pre
v
15
nex
t
pre
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L_S L_E temp
3)
falg
2 key 20
3 n
ext
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20
nex
t
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15
next
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L_S L_E
4)
flag
2 key 15
S
3 n
ext
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20
next
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15
nex
t
pre
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L_S L_E
Nil
flag
1 key 99
5)
S
procedure D_L_Delete ( var L_S,L_E: D_P; KEY:integer; var flag :char);
var
Temp , S:D_P;
begin
If L_S=nil then
flag:=‘3’ Else if KEY =L_S^.id then begin
Temp:=L_S;
L_S:=L_S^.next; ls^.prev:=nill ;
Dispose(Temp);
flag:=‘2’;
If L_s=nil then
L_E:=nil;
Else
L_s^.prev:=nil; end
Else if KEY = L_E^.id then
begin
Temp:=L_E;
L_E:=L_E^.prev; L_E^.next:=nil; Dispose(Temp);
Flag:=‘2’;
end
Else
begin
S:=L_S;
while (S<>nil) and (S^.id <> KEY ) do
S:=S^.next;
if S=nil then
flag:=‘1’; else
begin
S^.next^.prev:=S^.prev;
S^.prev^.next:=S^.next; Dispose(S);
flag:=‘ 2 ’; end;
end;
end; {procedure}
Homework:
+15 points
البحث عه عنصر ما في سلسة مترابطة اكتب اجرائية : مه طرفيه
Search( var L_s, L_E : D_P ; Key:integer;
var p: D_P ; var flag: char);
, بحيث تحفظ االجرائية مؤشر على مكان العنصر المراد -وجد العنصر-فشل) وتعيد محرف يعبر عه حالة البحث
( السلسلة فارغة
Group : group link
Mobile phone- Kinan : 0994385748
Facebook account : kinan’s account
2 bytes team
