t adt table - ittc

13
Tables, Priority Queues, Heaps Table ADT purpose, implementations Priority Queue ADT variation on Table ADT Heaps purpose, implementation heapsort EECS 268 Programming II 1 Table ADT A table in generic terms has M columns and N rows each row contains a separate record each column contains a different component, or field, of the same record Each table, or set of data, is also generally sorted, or accessed, by a key record component a single set of data can be organized into several different tables, sorted according to different keys Another common terms is a dictionary, whose entries are records, inserted and accessed according to a key value key may be a field in the record or not may also be used as frontends for data base access EECS 268 Programming II 2 ADT Table Example The ADT table, or dictionary Uses a search key to identify its items Its items are records that contain several pieces of data 3 ADT Table Operations A simple and obvious set of operations can be used for a wide range of program activities Create and Destroy Table instance Determine the number of items including zero Insert an item in a table using a key value Delete an item with a given key value Retrieve an item with a given key value Retrieve the items in the table (sorted or unsorted) Entries with identical key values maybe forbidden, but can be handled with a little imagination EECS 268 Programming II 4

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Page 1: t ADT Table - ITTC

Tab

les,

Pri

ori

ty Q

ue

ue

s, H

ea

ps

Tab

le A

DT

pu

rpo

se,

imp

lem

en

tati

on

s

Pri

ori

ty Q

ue

ue

AD

T

vari

ati

on

on

Ta

ble

AD

T

He

ap

s

pu

rpo

se,

imp

lem

en

tati

on

he

ap

sort

EE

CS

26

8 P

rogra

mm

ing I

I 1

Tab

le A

DT

A t

ab

le i

n g

en

eri

c te

rms

ha

s M

co

lum

ns

an

d N

ro

ws

ea

ch r

ow

co

nta

ins

a s

ep

ara

te r

eco

rd

ea

ch c

olu

mn

co

nta

ins

a d

iffe

ren

t co

mp

on

en

t, o

r fi

eld

, o

f

the

sa

me

re

cord

Ea

ch t

ab

le,

or

set

of

da

ta,

is a

lso

ge

ne

rall

y s

ort

ed

, o

r a

cce

sse

d,

by

a k

ey

re

cord

co

mp

on

en

t a

sin

gle

se

t o

f d

ata

ca

n b

e o

rga

niz

ed

in

to s

eve

ral

dif

fere

nt

tab

les,

so

rte

d a

cco

rdin

g t

o d

iffe

ren

t ke

ys

An

oth

er

com

mo

n t

erm

s is

a d

icti

on

ary

, w

ho

se e

ntr

ies

are

re

cord

s, in

sert

ed

an

d a

cce

sse

d a

cco

rdin

g t

o a

ke

y

va

lue

key

ma

y b

e a

fie

ld i

n t

he

re

cord

or

no

t

ma

y a

lso

be

use

d a

s fr

on

ten

ds

for

da

ta b

ase

acc

ess

EE

CS

268 P

rogra

mm

ing I

I 2

AD

T T

ab

le

Exa

mp

le

Th

e A

DT

ta

ble

, o

r d

icti

on

ary

Use

s a

se

arc

h k

ey

to

id

en

tify

its

ite

ms

Its

ite

ms

are

re

cord

s th

at

con

tain

se

vera

l p

iece

s o

f

da

ta

3

AD

T T

ab

le

Op

era

tio

ns

A s

imp

le a

nd

ob

vio

us

set

of

op

era

tio

ns

can

be

use

d

for

a w

ide

ra

ng

e o

f p

rog

ram

act

ivit

ies

Cre

ate

an

d D

est

roy

Ta

ble

inst

an

ce

De

term

ine

th

e n

um

be

r o

f it

em

s in

clu

din

g z

ero

Inse

rt a

n i

tem

in

a t

ab

le u

sin

g a

ke

y v

alu

e

De

lete

an

ite

m w

ith

a g

ive

n k

ey

va

lue

Re

trie

ve a

n i

tem

wit

h a

giv

en

ke

y v

alu

e

Re

trie

ve t

he

ite

ms

in t

he

ta

ble

(so

rte

d o

r u

nso

rte

d)

En

trie

s w

ith

id

en

tica

l ke

y v

alu

es

ma

yb

e f

orb

idd

en

, b

ut

can

be

ha

nd

led

wit

h a

lit

tle

im

ag

ina

tio

n

EE

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268 P

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ing I

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Page 2: t ADT Table - ITTC

Th

e A

DT

Ta

ble

5

vo

id t

ab

leIn

sert

(Ite

mT

yp

e&

ite

m):

st

ore

ite

m u

nd

er

its

key

bo

ole

an

ta

ble

De

lete

(Ke

yT

yp

e

ke

y_

va

lue

):

de

lete

ite

m w

ith

ke

y =

= k

ey

_va

lue

, if

p

rese

nt

Ite

mT

yp

e*

ta

ble

Re

trie

ve

(Ke

yT

yp

e

ke

y_

va

lue

):

retu

rn p

oin

ter

to i

tem

wit

h

key

==

key

_va

lue

vo

id t

rav

ers

eTa

ble

(Fu

nct

or

vis

ito

r):

F

un

cto

r: a

fu

nct

ion

-ob

ject

, m

uch

lik

e a

fn

po

inte

r

vis

ito

r is

exe

cute

d f

or

ea

ch n

od

e i

n t

ab

le

Th

e A

DT

Ta

ble

Ou

r ta

ble

ass

um

es

dis

tin

ct s

ea

rch

ke

ys

oth

er

tab

les

cou

ld a

llo

w d

up

lica

te s

ea

rch

ke

ys

Th

e traverseTable

op

era

tio

n v

isit

s ta

ble

ite

ms

in a

sp

eci

fie

d o

rde

r

on

e c

om

mo

n o

rde

r is

by

so

rte

d s

ea

rch

ke

y

a c

lie

nt-

de

fin

ed

vis

it f

un

ctio

n i

s su

pp

lie

d a

s a

n

arg

um

en

t to

th

e t

rave

rsa

l

call

ed

on

ce f

or

ea

ch ite

m in

th

e t

ab

le

EE

CS

268 P

rogra

mm

ing I

I 6

Se

lect

ing

an

Im

ple

me

nta

tio

n

Lin

ea

r im

ple

me

nta

tio

ns:

Fo

ur

cate

go

rie

s

Un

sort

ed

: a

rra

y b

ase

d o

r p

oin

ter

ba

sed

So

rte

d (

by

se

arc

h k

ey

): a

rra

y b

ase

d o

r p

oin

ter

ba

sed

EE

CS

26

8 P

rogra

mm

ing I

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Fig

ure

11

-3 T

he

da

ta m

em

be

rs fo

r tw

o s

ort

ed

lin

ea

r im

ple

me

nta

tio

ns o

f th

e A

DT

ta

ble

fo

r th

e d

ata

in F

igure

11-1

: (a

) arr

ay b

ased; (b

) poin

ter

based

Se

lect

ing

an

Im

ple

me

nta

tio

n

8

Fig

ure

11

-4 T

he

da

ta

me

mb

ers

fo

r a

bin

ary

se

arc

h

tre

e im

ple

me

nta

tion

of th

e

AD

T table

for

the d

ata

in

Fig

ure

11-1

No

nli

ne

ar

imp

lem

en

tati

on

s

Bin

ary

se

arc

h t

ree

imp

lem

en

tati

on

Off

ers

se

vera

l a

dva

nta

ge

s

ove

r li

ne

ar

imp

lem

en

tati

on

s

Page 3: t ADT Table - ITTC

Se

lect

ing

an

Im

ple

me

nta

tio

n

Th

e r

eq

uir

em

en

ts o

f a

pa

rtic

ula

r a

pp

lica

tio

n

infl

ue

nce

th

e s

ele

ctio

n o

f a

n i

mp

lem

en

tati

on

Qu

est

ion

s to

be

co

nsi

de

red

ab

ou

t a

n a

pp

lica

tio

n

be

fore

ch

oo

sin

g a

n i

mp

lem

en

tati

on

Wh

at

op

era

tio

ns

are

ne

ed

ed

?

Ho

w o

fte

n i

s e

ach

op

era

tio

n r

eq

uir

ed

?

Are

fre

qu

en

tly

use

d o

pe

rati

on

s e

ffic

ien

t g

ive

n a

pa

rtic

ula

r im

ple

me

nta

tio

n?

EE

CS

26

8 P

rogra

mm

ing I

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Co

mp

ari

ng

Lin

ea

r Im

ple

me

nta

tio

ns

Un

sort

ed

arr

ay

-ba

sed

im

ple

me

nta

tio

n

Inse

rtio

n is

ma

de

eff

icie

ntl

y a

fte

r th

e l

ast

ta

ble

it

em

in

an

arr

ay

De

leti

on

usu

all

y r

eq

uir

es

shif

tin

g d

ata

Re

trie

val r

eq

uir

es

a s

eq

ue

nti

al s

ea

rch

10

Fig

ure

11

-5a In

se

rtio

n fo

r u

nso

rte

d lin

ea

r im

ple

me

nta

tion

s: a

rra

y b

ase

d

Co

mp

ari

ng

Lin

ea

r Im

ple

me

nta

tio

ns

So

rte

d a

rra

y-b

ase

d i

mp

lem

en

tati

on

Bo

th i

nse

rtio

ns

an

d d

ele

tio

ns

req

uir

e s

hif

tin

g

da

ta

Re

trie

val

can

use

an

eff

icie

nt

bin

ary

se

arc

h

11

Fig

ure

11

-6a In

se

rtio

n fo

r so

rte

d lin

ea

r im

ple

me

nta

tio

ns: a

rra

y b

ase

d

Co

mp

ari

ng

Lin

ea

r Im

ple

me

nta

tio

ns

Un

sort

ed

po

inte

r-b

ase

d im

ple

me

nta

tio

n

No

da

ta s

hif

ts

Inse

rtio

n i

s m

ad

e e

ffic

ien

tly

at

the

be

gin

nin

g o

f a

li

nke

d l

ist

De

leti

on

re

qu

ire

s a

se

qu

en

tia

l se

arc

h

Re

trie

val r

eq

uir

es

a s

eq

ue

nti

al

sea

rch

12

Fig

ure

11

-5b

In

se

rtio

n fo

r u

nso

rte

d lin

ea

r im

ple

me

nta

tion

s: p

oin

ter

ba

se

d

Page 4: t ADT Table - ITTC

Co

mp

ari

ng

Lin

ea

r Im

ple

me

nta

tio

ns

So

rte

d p

oin

ter-

ba

sed

im

ple

me

nta

tio

n

No

da

ta s

hif

ts

Inse

rtio

ns,

de

leti

on

s, a

nd

re

trie

vals

ea

ch

req

uir

e a

se

qu

en

tia

l se

arc

h

13

Fig

ure

11

-6b

In

se

rtio

n fo

r so

rte

d lin

ea

r im

ple

me

nta

tion

s: p

oin

ter

ba

se

d

Se

lect

ing

an

Im

ple

me

nta

tio

n

Lin

ea

r

Ea

sy t

o u

nd

ers

tan

d c

on

cep

tua

lly

Ma

y b

e a

pp

rop

ria

te f

or

sma

ll t

ab

les

or

un

sort

ed

tab

les

wit

h f

ew

de

leti

on

s

No

nli

ne

ar

Is u

sua

lly

a b

ett

er

cho

ice

th

an

a l

ine

ar

imp

lem

en

tati

on

A b

ala

nce

d b

ina

ry s

ea

rch

tre

e

Incr

ea

ses

the

eff

icie

ncy

of

the

ta

ble

op

era

tio

ns

EE

CS

268 P

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mm

ing I

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Se

lect

ing

an

Im

ple

me

nta

tio

n

EE

CS

26

8 P

rogra

mm

ing I

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Fig

ure

11

-7 T

he

ave

rag

e-c

ase

ord

er

of th

e A

DT

ta

ble

op

era

tio

ns fo

r va

rio

us im

ple

me

nta

tio

ns

Se

lect

ing

an

Im

ple

me

nta

tio

n f

or

a

Pa

rtic

ula

r A

pp

lica

tio

n

Fre

qu

en

t in

sert

ion

s a

nd

in

fre

qu

en

t tr

ave

rsa

ls in

n

o p

art

icu

lar

ord

er

Un

sort

ed

lin

ea

r im

ple

me

nta

tio

n

Fre

qu

en

t re

trie

vals

So

rte

d a

rra

y-b

ase

d im

ple

me

nta

tio

n

Bin

ary

se

arc

h

Ba

lan

ced

bin

ary

se

arc

h t

ree

Fre

qu

en

t re

trie

vals

, in

sert

ion

s, d

ele

tio

ns,

tr

ave

rsa

ls

Bin

ary

se

arc

h t

ree

(p

refe

rab

ly b

ala

nce

d)

EE

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Page 5: t ADT Table - ITTC

Ge

ne

rali

zed

Da

ta S

et

Ma

na

ge

me

nt

Pro

ble

m o

f m

an

ag

ing

a s

et

of

da

ta ite

ms

occ

urs

m

an

y t

ime

s in

ma

ny

co

nte

xts

arb

itra

ry s

et

of

da

ta r

ep

rese

nte

d b

y a

n a

rbit

rary

ke

y

valu

e w

ith

in t

he

se

t

Str

ict

sep

ara

tio

n o

f th

e s

et

of

da

ta f

rom

th

e k

ey

h

elp

s w

ith

ab

stra

ctio

n a

nd

ge

ne

rali

zati

on

Da

ta S

et

cla

ss o

r st

ruct

ure

de

fin

ed

in a

pp

lica

tio

n t

erm

s

Co

nta

ine

r cl

ass

S

TL

term

ino

log

y

ho

lds

key

an

d d

ata

se

t it

em

s

EE

CS

26

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Ke

yed

Ba

se C

lass

Cre

ate

ba

se c

lass

fo

r

ass

oci

ati

ng

ke

y w

ith

an

arb

itra

ry it

em

Ma

inta

ins

key

ou

tsid

e t

he

ite

m f

ield

s

Ro

ws

of

Tab

le a

re d

eri

ved

cla

sse

s o

f th

is c

lass

Inse

rtin

g i

tem

in

Ta

ble

cre

ate

s in

sta

nce

of

de

rive

d

cla

ss a

nd

sto

res

it u

nd

er

key

#include <string>

using namespace std;

typedef string KeyType;

class KeyedItem

{

public:

KeyedItem() {}

KeyedItem(const KeyType&

keyValue)

: searchKey(keyValue){}

KeyType getKey() const {

return searchKey;

}

private:

KeyType searchKey;

};

EE

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268 P

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mm

ing I

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Tab

le I

tem

Cla

ss

Cre

ate

ta

ble

of

citi

es

ind

exe

d b

y c

ity

na

me

Mig

ht

cre

ate

str

uct

fo

r

ea

ch c

ity

na

me

, p

op

u.,

co

un

try

Or,

mig

ht

de

rive

th

is

cla

ss f

rom

Ke

yed

Ite

m

De

leg

ate

s ch

ose

n k

ey

to

ba

se c

lass

sto

rag

e

cla

ss C

ity

: p

ub

lic

Ke

yed

Ite

m

{ pu

bli

c:

C

ity

() :

Ke

yed

Ite

m()

{}

C

ity

(co

nst

str

ing

& n

am

e,

co

nst

str

ing

& c

try,

co

nst

in

t& n

um

)

:

Ke

yed

Ite

m(n

am

e),

co

un

try

(ctr

y),

po

p(n

um

) {}

st

rin

g c

ity

Na

me

() c

on

st;

in

t g

etP

op

ula

tio

n()

co

nst

;

vo

id s

etP

op

ula

tio

n(i

nt

ne

wP

op

);

pri

vate

:

//

cit

y's

na

me

is

sea

rch

-ke

y v

alu

e

st

rin

g c

ou

ntr

y;

in

t

po

p;

};

EE

CS

26

8 P

rogra

mm

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A S

ort

ed

Arr

ay

-Ba

sed

Im

ple

me

nta

tio

n

of

the

AD

T T

ab

le

De

fau

lt c

on

stru

cto

r a

nd

vir

tua

l d

est

ruct

or

Co

py

co

nst

ruct

or

sup

pli

ed

by

th

e c

om

pil

er

Pu

bli

c m

eth

od

s a

re v

irtu

al

Pro

tect

ed

me

tho

ds:

se

tSiz

e,

setI

tem

, a

nd

po

siti

on

EE

CS

268 P

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Page 6: t ADT Table - ITTC

A B

ina

ry S

ea

rch

Tre

e I

mp

lem

en

tati

on

of

the

AD

T T

ab

le

Re

use

s BinarySearchTree

An

in

sta

nce

is

a p

riva

te d

ata

me

mb

er

De

fau

lt c

on

stru

cto

r a

nd

vir

tua

l d

est

ruct

or

Co

py

co

nst

ruct

or

sup

pli

ed

by

th

e c

om

pil

er

Pu

bli

c m

eth

od

s a

re v

irtu

al

Pro

tect

ed

me

tho

d: setSize

EE

CS

26

8 P

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mm

ing I

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Pri

ori

ty Q

ue

ue

Bin

ary

Se

arc

h T

ree

is a

n e

xce

lle

nt

da

ta s

tru

ctu

re,

bu

t n

ot

alw

ays

si

mp

le i

n c

on

cep

t a

nd

im

ple

me

nta

tio

n

BS

T s

up

po

rts

ma

ny

use

ful

op

era

tio

ns

we

ll

inse

rt,

de

lete

, d

ele

teM

ax,

de

lete

Min

, se

arc

h,

sea

rch

Ma

x,

sea

rch

Min

, so

rt

eff

icie

nt

ave

rag

e c

ase

be

ha

vio

r T

(n)

= O

(lo

g n

)

Ho

we

ver,

BST

is

no

t g

oo

d i

n a

ll r

esp

ect

s fo

r a

ll

pu

rpo

ses

bri

ttle

wit

h r

esp

ect

to

ba

lan

ce

wo

rst

case

T(n

) =

O(n

)

Ba

lan

ced

Tre

es

are

po

ssib

le b

ut

mo

re c

om

ple

x

EE

CS

268 P

rogra

mm

ing I

I 22

Pri

ori

ty Q

ue

ue

Pri

ori

ty Q

ue

ue

se

ma

nti

cs a

re u

sefu

l w

he

n i

tem

s a

re a

dd

ed

to

th

e s

et

in a

rbit

rary

ord

er,

bu

t a

re

rem

ove

d in

eit

he

r a

sce

nd

ing

or

de

sce

nd

ing

p

rio

rity

ord

er

pri

ori

ty c

an

ha

ve a

fle

xib

le d

efi

nit

ion

an

y p

rop

ert

y o

f th

e s

et

ele

me

nts

imp

osi

ng

a t

ota

l o

rde

r o

n t

he

se

t m

em

be

rs

If o

nly

a p

art

ial

ord

er

is i

mp

ose

d (

mu

ltip

le ite

ms

wit

h

eq

ua

l pri

ori

ty)

a s

eco

nd

ary

tie

bre

ak

ing

ru

le c

an

be

u

sed

to

cre

ate

a t

ota

l o

rde

r

EE

CS

26

8 P

rogra

mm

ing I

I 23

Pri

ori

ty Q

ue

ue

Th

e d

ele

tio

n o

pe

rati

on

fo

r a

pri

ori

ty q

ue

ue

is

dif

fere

nt

fro

m t

he

on

e f

or

a t

ab

le

ite

m r

em

ove

d i

s th

e o

ne

ha

vin

g t

he

hig

he

st

pri

ori

ty v

alu

e

Pri

ori

ty q

ue

ue

s d

o n

ot

ha

ve r

etr

ieva

l an

d

tra

vers

al o

pe

rati

on

s

EE

CS

268 P

rogra

mm

ing I

I 24

Page 7: t ADT Table - ITTC

AD

T P

rio

rity

Qu

eu

e

25

Fig

ure

11

-8 U

ML d

iag

ram

fo

r th

e c

lass P

rio

rity

Qu

eu

e

Th

e A

DT

Pri

ori

ty Q

ue

ue

:

Po

ssib

le I

mp

lem

en

tati

on

s

So

rte

d l

ine

ar

imp

lem

en

tati

on

s

Ap

pro

pri

ate

if

the

nu

mb

er

of

ite

ms

in t

he

pri

ori

ty

qu

eu

e i

s sm

all

Arr

ay-b

ase

d i

mp

lem

en

tati

on

Ma

inta

ins

the

ite

ms

sort

ed

in

asc

en

din

g o

rde

r o

f

pri

ori

ty v

alu

e

ite

ms[

size

- 1

] h

as

the

hig

he

st p

rio

rity

EE

CS

268 P

rogra

mm

ing I

I 26

Fig

ure

11

-9a A

n a

rra

y-b

ase

d im

ple

me

nta

tio

n o

f th

e A

DT

prio

rity

qu

eu

e

Th

e A

DT

Pri

ori

ty Q

ue

ue

:

Po

ssib

le I

mp

lem

en

tati

on

s

So

rte

d l

ine

ar

imp

lem

en

tati

on

s (c

on

tin

ue

d)

Po

inte

r-b

ase

d i

mp

lem

en

tati

on

Ma

inta

ins

the

ite

ms

sort

ed

in

de

sce

nd

ing

ord

er

of

pri

ori

ty v

alu

e

Ite

m h

av

ing

th

e h

igh

est

pri

ori

ty is

at

be

gin

nin

g o

f li

nke

d

list

EE

CS

26

8 P

rogra

mm

ing I

I 27

Fig

ure

11

-9b

A

po

inte

r-ba

se

d im

ple

me

nta

tio

n o

f th

e A

DT

prio

rity

qu

eu

e

Th

e A

DT

Pri

ori

ty Q

ue

ue

:

Po

ssib

le I

mp

lem

en

tati

on

s

Bin

ary

se

arc

h t

ree

im

ple

me

nta

tio

n

Ap

pro

pri

ate

fo

r a

ny

pri

ori

ty q

ue

ue

Larg

est

ite

m i

s ri

gh

tmo

st a

nd

ha

s a

t m

ost

on

e

chil

d

28

Fig

ure

11

-9c A

bin

ary

se

arc

h tre

e

imp

lem

en

tatio

n o

f th

e

AD

T p

rio

rity

qu

eu

e

Page 8: t ADT Table - ITTC

Th

e A

DT

Pri

ori

ty Q

ue

ue

:

He

ap

Im

ple

me

nta

tio

n

A h

ea

p i

s a

co

mp

lete

bin

ary

tre

e

tha

t is

em

pty

, O

R

wh

ose

ro

ot

con

tain

s a

se

arc

h k

ey

>=

th

e s

ea

rch

ke

y in

e

ach

of

its

chil

dre

n,

an

d w

ho

se r

oo

t h

as

he

ap

s a

s it

s su

btr

ee

s

He

ap

is

the

be

st a

pp

roa

ch b

eca

use

it

is t

he

mo

st

eff

icie

nt

for

the

sp

eci

fic

PQ

se

ma

nti

cs

He

ap

pro

vid

es

a p

art

iall

y o

rde

red

tre

e

avo

ids

bri

ttle

ne

ss o

f B

ST

an

d h

as

low

er

ove

rhe

ad

th

an

b

ala

nce

d s

ea

rch

tre

es

EE

CS

26

8 P

rogra

mm

ing I

I 29

He

ap

s

No

te:

Th

e s

ea

rch

ke

y in

ea

ch h

ea

p n

od

e i

s >

= t

he

se

arc

h

ch

ild

ren

req

uir

ed

re

lati

on

ship

EE

CS

268 P

rogra

mm

ing I

I 30

He

ap

s

A m

axi

mu

m,

bin

ary

, h

ea

p H

is

a c

om

ple

te b

ina

ry

tre

e s

ati

sfy

ing

th

e h

ea

p-o

rde

red

tre

e p

rop

ert

y:

Co

mp

lete

: E

very

le

vel c

om

ple

te,

exc

ep

t p

oss

ibly

th

e

last

, a

nd

all

le

ave

s a

re a

s fa

r le

ft a

s p

oss

ible

He

ap

Ord

ere

d:

Pri

ori

ty o

f a

ny

no

de

is

>=

pri

ori

ty o

f a

ll

its

de

sce

nd

an

ts

ma

xim

um

ele

me

nt

of

set

is t

hu

s a

t ro

ot

A m

inim

um

he

ap

en

sure

s th

at

all

no

de

s h

ave

p

rio

rity

va

lue

s <

= a

ll its

de

sce

nd

an

ts

min

imu

m e

lem

en

t a

t ro

ot

E

EC

S 2

68 P

rogra

mm

ing I

I 31

He

ap

A

DT

EE

CS

268 P

rogra

mm

ing I

I 32

Fig

ure

11

-10 U

ML d

iag

ram

fo

r th

e c

lass H

ea

p

Page 9: t ADT Table - ITTC

He

ap

I

mp

lem

en

tati

on

Co

nsi

de

rin

g t

yp

ica

l h

ea

p o

pe

rati

on

s, f

or

exa

mp

le,

inse

rt in

to h

ea

p

Re

sult

mu

st b

e a

co

mp

lete

tre

e s

ati

sfy

ing

th

e h

ea

p

pro

pe

rty

th

at

all

no

de

s a

re >

= d

esc

en

da

nts

Tw

o s

tep

in

sert

pro

cess

wo

rks

we

ll

com

ple

te b

ina

ry t

ree

rest

ruct

ure

H t

o m

ake

it

sati

sfy

th

e h

ea

p-o

rde

red

pro

pe

rty

Tw

o s

tep

re

mo

ve

clie

nt

cod

e s

ave

ro

ot

valu

e f

or

use

-ord

er

Re

stru

ctu

re H

to

mig

rate

/pe

rco

late

ne

w r

oo

t to

th

e c

orr

ect

tr

ee

lo

cati

on

EE

CS

26

8 P

rogra

mm

ing I

I 33

He

ap

I

mp

lem

en

tati

on

Tra

vers

al o

f th

e i

nse

rte

d n

od

e t

o i

ts p

rop

er

pla

ce r

eq

uir

es

at

mo

st O

(lo

g n

) o

pe

rati

on

s

sin

ce t

he

he

igh

t o

f a

co

mp

lete

bin

ary

tre

e i

s

O

(lo

g n

)

EE

CS

268 P

rogra

mm

ing I

I 34

He

ap

I

mp

lem

en

tati

on

De

leti

on

is

sim

ila

r

alw

ays

de

lete

s th

e r

oo

t o

f th

e t

ree

, le

ft w

ith

tw

o

dis

join

t su

btr

ee

s

pla

ce i

tem

in

la

st n

od

e i

n t

he

ro

ot

ou

t o

f p

lace

ite

m i

n r

oo

t n

od

e s

ho

uld

pe

rco

late

do

wn

to

its

pro

pe

r p

osi

tio

n

O(l

og

n)

EE

CS

26

8 P

rogra

mm

ing I

I 35

He

ap

I

mp

lem

en

tati

on

Da

ta s

tru

ctu

re s

uit

ab

le f

or

he

ap

im

ple

me

nta

tio

n m

ust

su

pp

ort

eff

icie

nt

de

term

ina

tio

n o

f w

he

re n

ext

an

d l

ast

sl

ots

in

a c

om

ple

te t

ree

are

lo

cate

d f

or

inse

rt a

nd

de

lete

, re

spe

ctiv

ely

sup

po

rt e

ffic

ien

t p

erc

ola

tio

n o

f m

isp

lace

d n

od

es

Pe

rco

lati

on

do

wn

is

sim

ple

usi

ng

sta

nd

ard

ch

ild

re

fere

nce

s a

nd

co

mp

ari

son

of

pa

ren

t to

ch

ild

va

lue

s

Pe

rco

lati

on

up

is

alm

ost

as

sim

ple

, b

ut

req

uir

es

a

pa

ren

t re

fere

nce

at

ea

ch n

od

e

Kn

ow

ing

th

e la

st o

ccu

pie

d a

nd

ne

xt o

pe

n s

lots

un

de

r d

iffe

ren

t d

ata

str

uct

ure

s is

mo

re s

ub

tle

un

de

r so

me

d

ata

str

uct

ure

s th

an

oth

ers

EE

CS

268 P

rogra

mm

ing I

I 36

Page 10: t ADT Table - ITTC

He

ap

I

mp

lem

en

tati

on

Po

inte

r b

ase

d h

ea

ps

req

uir

e t

wo

ch

ild

an

d o

ne

pa

ren

t p

oin

ter

at

ea

ch n

od

e

can

use

ad

dit

ion

al st

ate

info

rma

tio

n t

o t

rack

loca

tio

n o

f n

ext

an

d l

ast

co

mp

lete

tre

e s

lots

Arr

ay

ba

sed

he

ap

imp

lem

en

tati

on

sim

pli

fie

s p

are

nt

a

nd

ch

ild

re

fere

nce

s b

y m

ak

ing

th

em

ca

lcu

late

d

low

ers

sp

ace

ove

rhe

ad

no

t cl

ea

r e

xecu

tio

n t

ime

wo

uld

be

lo

we

r a

rra

y in

de

x ca

lcu

lati

on

vs.

po

inte

r a

cce

ss

Sim

ila

rly,

lo

cati

on

of

the

ne

xt a

nd

la

st s

lots

fo

r th

e

com

ple

te t

ree

ca

n b

e c

alc

ula

ted

fro

m t

he

nu

mb

er

of

no

de

s in

th

e t

ree

, w

hic

h is

sim

ple

to

tra

ck

EE

CS

26

8 P

rogra

mm

ing I

I 37

He

ap

A

rra

y I

mp

lem

en

tati

on

In a

n a

rra

y r

ep

rese

nta

tio

n o

f a

bin

ary

tre

e T

Ro

ot

of

T i

s a

t A

[0]

left

an

d r

igh

t ch

ild

ren

of

A[i

] a

re a

t A

[2i+

1]

an

d

A[2

i+2

]

pa

ren

t o

f a

no

de

A[i

] is

at

A[(

i-1

)/2

]

for

n>

1,

A[i

] is

a l

ea

f if

f 2

i>n

in a

he

ap

wit

h n

ele

me

nts

th

e l

ast

ele

me

nt

of

the

com

ple

te b

ina

ry t

ree

is

at

A[n

-1]

an

d t

he

ne

xt

ele

me

nt

(ele

me

nt

n+

1)

wil

l b

e a

dd

ed

at

A[n

]

EE

CS

268 P

rogra

mm

ing I

I 38

He

ap

A

rra

y I

mp

lem

en

tati

on

An

arr

ay

-ba

sed

re

pre

sen

tati

on

is

att

ract

ive

Co

nst

an

t M

AX

_H

EA

P

Da

ta m

em

be

rs

ite

ms:

an

arr

ay

of

he

ap

ite

ms

size

: a

n in

teg

er

eq

ua

l to

th

e c

urr

en

t n

um

be

r o

f it

em

s in

th

e h

ea

p

EE

CS

26

8 P

rogra

mm

ing I

I 39

He

ap

A

rra

y I

mp

lem

en

tati

on

he

ap

De

lete

op

era

tio

n w

ith

arr

ays

Ste

p 1

: R

etu

rn t

he

ite

m i

n t

he

ro

ot

roo

tIte

m =

ite

ms[

0]

EE

CS

268 P

rogra

mm

ing I

I 40

Fig

ure

11

-12a D

isjo

int h

ea

ps

Page 11: t ADT Table - ITTC

He

ap

A

rra

y I

mp

lem

en

tati

on

Ste

p 2

: C

op

y t

he

ite

m f

rom

th

e l

ast

no

de

in

to

the

ro

ot:

ite

ms[

0]=

ite

ms[

size

-1]

Ste

p 3

: R

em

ove

th

e l

ast

no

de

: --

size

Re

sult

s in

a s

em

ihe

ap

EE

CS

26

8 P

rogra

mm

ing I

I 41

Fig

ure

11

-12

b A

se

mih

ea

p

He

ap

A

rra

y I

mp

lem

en

tati

on

Ste

p 3

: Tr

an

sfo

rm t

he

se

mi-

he

ap

ba

ck i

nto

a

he

ap

use

th

e r

ecu

rsiv

e a

lgo

rith

m h

ea

pR

eb

uil

d

the

ro

ot

valu

e t

rick

les

do

wn

th

e t

ree

un

til

it i

s n

ot

ou

t o

f p

lace

if t

he

ro

ot

ha

s a

sm

all

er

sea

rch

ke

y t

ha

n t

he

la

rge

r o

f

the

se

arc

h k

eys

of

its

chil

dre

n,

swa

p t

he

ite

m in

th

e

roo

t w

ith

th

at

of

the

la

rge

r ch

ild

EE

CS

268 P

rogra

mm

ing I

I 42

A H

ea

p I

mp

lem

en

tati

on

of

the

AD

T

Pri

ori

ty Q

ue

ue

Pri

ori

ty-q

ue

ue

op

era

tio

ns

an

d h

ea

p

op

era

tio

ns

are

an

alo

go

us

the

pri

ori

ty v

alu

e i

n a

pri

ori

ty-q

ue

ue

co

rre

spo

nd

s

On

e i

mp

lem

en

tati

on

ha

s a

n i

nst

an

ce o

f th

e H

ea

p c

lass

as

a p

riva

te d

ata

me

mb

er

me

tho

ds

call

an

alo

go

us

he

ap

op

era

tio

ns

EE

CS

26

8 P

rogra

mm

ing I

I 43

A H

ea

p I

mp

lem

en

tati

on

of

the

AD

T

Pri

ori

ty Q

ue

ue

dis

ad

van

tag

e

ma

xim

um

siz

e

ad

van

tag

e

a h

ea

p i

s a

lwa

ys b

ala

nce

d

An

oth

er

imp

lem

en

tati

on

a h

ea

p o

f q

ue

ue

s

use

ful

wh

en

a f

init

e n

um

be

r o

f d

isti

nct

pri

ori

ty

valu

es

are

use

d,

wh

ich

ca

n r

esu

lt i

n m

an

y i

tem

s h

av

ing

th

e s

am

e p

rio

rity

va

lue

EE

CS

268 P

rogra

mm

ing I

I 44

Page 12: t ADT Table - ITTC

He

ap

sort

Str

ate

gy

tra

nsf

orm

th

e a

rra

y in

to a

he

ap

rem

ove

th

e h

ea

p's

ro

ot

(th

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He

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268 P

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mm

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Fig

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11

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Su

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Page 13: t ADT Table - ITTC

Su

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A p

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