Date. Structures. Housekeeping. functions stacks Centro) Last Ctt odds tends

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1 Date Structures Housekeeping functions stacks Centro) Last Ctt odds tends

2 Today HW due Thursday Lab tomorrow Check repo for grade file

3 Pantoslnadass Points are especially useful in classes Often we don't know the details of variables private at time of object creation Example Using an At time of declaration array need type var name size

4 Anexampte A simple vector class vector in 1122 < 25 > vector in 1124 < 0 10 s > So size is not fixed! How to make a class? class private int size ; Float Vee { My float * a ; Aponte to ana~ ftphmgiiasoaa#eethtoaeiid " a [ 03=12 ; FEE inmnftnoatvavtll ; VESEY

5 Accessing Pointers any array to an array arrays are special in fact is a to pointer the 1st in spot the just ( no * or needed ) array Et " Write a function to allow [ ] notation so xci ] ik element gives in the vector pubic lkonstncton n 3 at& operator [ ] ( int i){ if ( i < size ) dsrqtwn a < error > [ if ;

6 Garbagecokechomin Python data that Is Longer in use are destroyed LI xd overhead automatically Xts 11=10 sn#typros=euoasyuser Cord slows language down

7 Ctt Value a reference variables are destroyed their scope at the end of Standard variables are just a label attached to data data is deal located So those are spaces now free again Problems Pointers The pointer is destroyed not underlying data Fleck 19=5273 around 3/1 5 deakocated mtntmec#enwintgtpkfp=fas ; use new Rud If you you must that data explicitly destroy

8 Housekeeping ' functions Basically need to deal itthese pointer issues 1 Copy Constructor Say I call Myfloatvec C ; Hadd data to c constructor due Default result? Copy tmykoatueebat# constructor takes each 1069 private variable bae#gsbfs*iosf%fezt sets them =

9 So overriding this class Mytloatvec { Mother things b s Public #@y io nfyfloatvecetmyfloathec@idsizeothers } off ize ; T cnetgs#s9eeg?d+)rdoaa local AED = other agg " other ' is gone ; variable result deep copies

10 2 The = operator Same issue Myfloatvec dak 11pct X in b ; ; xeb }t by defaults Feet ftpaneyeif doqsopsyhdlow 938 ygoo Fryman's

11 So in the ebss { if operator ( const (ths &otr){ delete [ ] a myftattefothef size = other my# & z z a size ; = new float [ size ] ; for ( uat i=o;i< site ; itt ) a [ if return * this ; other a[i]g (this is like self in pylhon )

12 3 The destructor Finally object when int main C) { you Float Vec ; my acde an }** destroyed me to is reatgdgagtokfo whthappens # #f a5%yb##l air

13 E " in class ~My Float Vecc ) { ] a ; z top 0# site " of new " compiler tells point a what follow tdeallocak points variable Housekeeping Any class 4 fans a new needs all often

14 A note on our first data structure Stacks a way a Io List store Preuosly visited web pages Et Previous changes to a word document undo pgr#fpnshufo #

15 The stack ADT ushce ) adds eto top pop C) removes top Also sized empty C) top " } returns top clout removing see cpluspluscom

16 push Example int main C) { stack < int > myskck ; for ( int in 10 ; ic 20 ;it=2 ) } mystack push mystackapopc ) ; mystack Coutu ( i ) ; 400 ) ; mystack top C) aendl ; See cplusptuscom for lab tomorrow on stacks This week we 'll code our own!

17 Meanwhile A few more Ctt odds ends Enum ' Than Color { RED Blue GREEN}j Color Color Sky = BLUES grass = GREEN ; if ky== Blue ) Coutu " It's a nice day! " ; Reason

18 Struts useful for simple Collections of date z enum Meal Pref { NORMAL VEG KOSHER} ; struct Passenger { string name ; Mealpref foodpref ; bool int int main C) { is FrequentFlyer ; freqflyernum ; Passenger pass ; pass name = " Erin Passenger pass 2={ VEG true ; Chambers 'S " John Smith 's i }

19 Templates # IF went a function to work for multple like MB + floats temples template < T min ( Ta } then if ( a < b) else return return data use type name T > a bs T b) { ; types

20 Tempktesinckssesthese we in important why? data structures Actually you'll use these in the steak lab

21 Errorltandhg In Ctt we handle errors by throwing exceptions ( Exceptions are actually ) own classes also then Recall What in Python? were the ones I 'll base mine of Ctt 's default ones # include < stdexapt > see cplusplus for details

22 Sometimes In Python In Ctt In general to avoid crashing

23 Reading input example

Data Structures. end of Ctt. Simple lists

Data Structures. end of Ctt. Simple lists Data Structures end of Ctt Simple lists Update HW due tomorrow Availability today/ tomorrow In 12 1230 or 130 2 tutoring afternoon Git Friday a Remove some code want a laptop working now! if you He Csa