C++ ReviewC++ Review11Cpt S 223. School of EECS, WSUPurpose of Review Review some basic C++Familiarize us with Weiss’sstyleFamiliarize us with Weisss style Some good coding practicesdf flf Introduce specific constructs useful for implementing data structures STL overviewNote: Not all slides shown in PPT;2 Refer to the PDF version of slides for thatCpt S 223. School of EECS, WSUClass The Class defines the data structure and the operations that access and pmanipulate it Member data Member functions or methods Encapsulation = data + methods Information hiding Public vs. private vs. protected33Cpt S 223. School of EECS, WSUCommentConstructorConstructor4Cpt S 223. School of EECS, WSUEncapsulInformationHidingation5Cpt S 223. School of EECS, WSUSeparation of Interface and Implementation Interface (.h) fileDefines class and its member data andDefines class and its member data and functionsImplementation ( cc or cpp) fileImplementation (.cc or .cpp) file Provides implementations of member functionsfunctions6Cpt S 223. School of EECS, WSUExtra Syntax Default parametersInitializer listInitializer list Explicit constructorbf Constant member function Accessor methods Mutator methods7Cpt S 223. School of EECS, WSUDefault ExplicitParameterspConstructorInitializerLi tAccessorListAccessorMutatorIntCell obj;obj = 37;Mutator8Cpt S 223. School of EECS, WSUPreprocessorDirectives9IntCell class interface in file IntCell.h.Cpt S 223. School of EECS, WSUPreprocessorDirectiveScopinggOperatorClassName::member10IntCell class implementation in file IntCell.cpp.Cpt S 223. School of EECS, WSUPreprocessorDirectivesDirectivesDefault classProgram using IntCell class in file TestIntCell.cpp.11Cpt S 223. School of EECS, WSUC++ Details PointersParameter passingParameter passing Return passingfbl Reference variables Destructor, copy constructor, operator=12Cpt S 223. School of EECS, WSUPointersAddress-of operator &IntCell icObj;IntCell *m = & icObj;No garbage collection in C++13Cpt S 223. School of EECS, WSUParameter Passing Call by valueSmall objects not altered by functionSmall objects not altered by function Call by constant referenceLarge objects not altered by functionLarge objects not altered by function Call by reference Objects altered by functiondouble avg (const vector<int> & arr int n bool & errorFlag);14double avg (const vector<int> & arr, int n, bool & errorFlag);Cpt S 223. School of EECS, WSU15What’s wrong with this code?Return passingCpt S 223. School of EECS, WSUReference Variables As seen, can be used for parameter passingpassing Also used as synonyms for the objects they referencethey reference Avoid cost of copyingstring x = findMax (a);cout << x << endl;const string & x = findMax (a);cout << x << endl;16Cpt S 223. School of EECS, WSUDestructor Default definitions for all classesDestructorDestructor Called when object goes out of scope or subject to a delete By default, calls destructor on all data membersMi ht t tdlbj t t dMight want to delete objects created using newMight want to close any opened files17Might want to close any opened files.Cpt S 223. School of EECS, WSUCopy Constructor Copy constructor Declaration duringinitializationIntCellB=C;IntCell B = C; IntCell B (C); Object passed using call by value (instead of by &orconst &)or const &) Object returned by value (instead of by & or const & )Simple assignment for all members withSimple assignment for all members with primitive data types (e.g., int, double, …) Calls copy constructors on all member objects18py jCpt S 223. School of EECS, WSUoperator= Copy assignment operator: operator=Called when objects on both sides ofCalled when objects on both sides of assignment already constructed E.g.,IntCell B(0);g,IntCell C(1);B = C; By default, operator= called on each data member of objects19data member of objectsCpt S 223. School of EECS, WSU20Default destructor, copy constructor and operator= for IntCellCpt S 223. School of EECS, WSUProblems with Defaults21Cpt S 223. School of EECS, WSUProblems with DefaultsOt t?22Output?Cpt S 223. School of EECS, WSUFixing the Defaults23Cpt S 223. School of EECS, WSUTemplates Designing type-independent data structures and algorithmsstructures and algorithms Function templatesClass templatesClass templates24Cpt S 223. School of EECS, WSUFunction Templates25Cpt S 223. School of EECS, WSUFunction Templates26Cpt S 223. School of EECS, WSUClass Templates27Cpt S 223. School of EECS, WSUClass Templates28Cpt S 223. School of EECS, WSUC++ Standard Template Library: BasicsSGI’s web reference:SGIs web reference:http://www.sgi.com/tech/stl/29Cpt S 223. School of EECS, WSUKey concepts ContainersIteratorsIterators30Cpt S 223. School of EECS, WSUExample Problem Find the maximum in an (i) linked list of integers(i) linked list of integers (ii) array of integers31Cpt S 223. School of EECS, WSUCoding using STL Linked List Array*curr;*curr;Do you see the advantage of using iterators in the above example?32Do you see the advantage of using iterators in the above example?Cpt S 223. School of EECS, WSUList of containersSTL container: Data structure that it implements:vectorArrayvectorArraylistDoubly-linked listslistSingly-linked listgyqueueFIFO structurestackLIFO structuredequeArray-like structure with efficient insertion & removal at both endssetSet of unique elements33qCpt S 223. School of EECS, WSUAPI for the containersFunction: Purpose:push_front Inserts elements before the first (not available for vector)pop frontRemoves the first element (not available for vector)pop_frontRemoves the first element (not available for vector)push_back Appends element at the endpop_back Removes element from the endemptyBoolean indicating if the container is empty pyoo a d a g o a s p ysizeReturns number of elementsinsertInsert an element in a positioneraseRemoves an element at a positionclearRemoves all elementsresizeResizes the containerfrontReturns a reference to the first element34BackReturns a reference to the last element[] Subscripting access without bounds checkingatSubscripting access with bounds checkingCpt S 223. School of EECS, WSUSummary Basic C++TemplatesTemplates Tools for easing the design of type-independent data structures andindependent data structures and algorithmsPlease refer to