会计学outlinesclassRational{//数据成员：分子,分母(fēnmǔ)；intfm;intfz;//成员函数：输出信息；voidshow();};classRational{//增加成员函数(hánshù)：初始化数据成员};classRational{//增加成员(chéngyuán)函数：相乘multiply();};//rational.hclassRational{//数据成员(chéngyuán)声明；//成员(chéngyuán)函数声明;};User-defined(programmer-defined)types:classesData(datamembers)Functions(memberfunctionsormethods)Classinstance:objectclassTypeName{...};Memberaccessspecifierspublic:Accessiblewhereverobjectofclassinscopeprivate:Accessibleonlytomemberfunctionsofclassprotected:ObjectsofclassAfterclassdefinition,ClassnameisnewtypespecifierOperatorstoaccessclassmembersoperator(.)——ObjectorReferencetoobjectoperator(->)——PointersClassscopeDatamembers,memberfunctionsWithinclassscopeImmediatelyaccessiblebyallmemberfunctionsReferencedbynameOutsideclassscopeReferencedthroughhandlesObjectname,referencetoobject,pointertoobjectMemberfunctionsdefinedoutsideclassBinaryscoperesolutionoperator(::)FormatfordefiningmemberfunctionsReturnTypeClassName::MemberFunctionName(){…}ConstructorfunctionSamenameasclassInitializesdatamembersCalledwhenobjectinstantiatedSeveralconstructorsFunctionoverloadingNoreturntypeDestructorfunctionSamenameasclass，Precededwithtilde(~)Noreturntype&&NoargumentsCannotbeoverloadedPerforms“terminationhousekeeping”friendFunctionsclassRational{//增加(zēngjiā)友元函数：相乘rationalmultiply();};通过函数调用来实现(shíxiàn)相乘，仍然不直观classRational{//增加友元函数：重载(zhònɡzǎi)乘法运算符*//friendRationalmultiply(Rationalx,Rationaly);};Overloaded<<operatorLeftoperandoftypeostream&Suchascoutobjectincout<<classObjectSimilarly,overloaded>>needsistream&Thus,bothmustbenon-memberfunctionsclassRational{//增加友元函数(hánshù)：重载<<运算符friendostream&operator<<(ostream&,Rationalx);};ostream&operator<<(ostream&output,Rationalx){output<<x.fz<<"/"<<x.fm;returnoutput;}intmain(){cout<<a<<b;}Overloaded>>operatorLeftoperandoftypeistream&Suchascoutobjectincin>>classObjectmustbefriendfunctionsclassRational{//增加友元函数(hánshù)：重载>>运算符frie