"Thinkinginc++" 60, embedded iterator

Embedded iterators

NestedSmartPointer.cpp

/*** book: "thinkinginc++" * Function: Embedded iterator * Time: September 26, 2014 10:03:03* Author: cutter_point*/#include <iostream> #include < Vector> #include ". /require.h "UsingNamespace std;    class obj{static int i, J;    Static variable public:void f () {Cout<<i++<<endl;} void G () {cout<<j++<<endl;}}; int obj::i=47;intobj::j=11;     classobjcontainer{vector<obj*> A;//This is a container that holds the OBJ class public:void Add (obj* obj) {a.push_back (obj);} Class Smartpointer;    Declare a class, for the following write is friend friend Smartpointer;        A statement is a friend's premise that the class Smartpointer {objcontainer& oc must be known to be present;    unsigned int index;         Public:smartpointer (objcontainer& OBJC): OC (OBJC) {index=0;}            BOOL operator++ ()//prefix + + {if (index >= oc.a.size ()) Returnfalse;    if (oc.a[++index] = = 0) returnfalse;        This is to determine whether the + + operation has already executed the//index data value has changed the return true;    } bool operator++ (int) {return operator++ (); This postThe results of the prefix + + are the same as the prefixes} obj* operator-> () const//plays, which is the key to this sectionto learning, operator overloading {require (OC).            A[index]! = 0, "Zero value returned by smartpointer::operator-> ()"); return Oc.a[index];     Returns the index data of the array}}; Here is a function, just like the one used by the C + + standard library, in order to return to the place where index 0 is smartpointer begin () {returnsmartpointer (*this);}};    int main () {const int sz=10;    OBJ O[sz];    Objcontainer OC;    for (int i=0; i<sz; ++i) Oc.add (&o[i]);     Objcontainer::smartpointer Sp=oc.begin ();        do {sp->f ();    Sp->g ();     }while (++SP); return 0;}

"Thinkinginc++" 60, embedded iterator