C + + Stl:vector implementation

Practice a pitch, primarily by using placement new to create objects on raw memory. Halfway MD Interview phone come, quickly archive, see Java Dafa

#include <iostream>#include<cstdlib>#include<vector>#include<algorithm>using namespacestd;classObject { Public:    Static intcount; Public:    intCurrent ; intID; Object (inti) {ID=i; Current= count++; cout<<"object["<<id<<"] Create:"<<current<<Endl; }        ~Object () {cout<<"object["<<id<<"] Destroy:"<<current<<Endl; } Object (Constobject&obj) { Current= count++; ID=obj.id; cout<<"object["<<id<<"] Copied:"<<current<<"Old :"<<obj.current<<Endl; }};intObject::count =0; template<classT>classMyvector { Public: typedef T VALUE_TYPE; typedef value_type*pointer; typedef value_type*iterator; typedef value_type&reference;    typedef size_t SIZE_TYPE;    typedef ptrdiff_t DIFFERENCE_TYPE; Private: iterator start;    Iterator finish; Iterator space_end; Public: Myvector () {Start=NULL; Space_end=NULL; Finish=NULL; } size_type Capacity () {returnSpace_end-start;} Size_type size () {returnFinish-start;} BOOLEmpty () {returnStart = =finish;} Iterator begin () {returnstart;} Iterator End () {returnfinish;} Referenceoperator[] (intIDX) {returnStart[idx];} Reference Front () {return*start;} Reference back () {return* (finish-1);} voidclear () {}voidPop_back () {if(Start >=finish) {            return; } Finish--; Finish->~T (); }        voidPush_back (Constt&x) {if(Finish <space_end) {            //Placement New            New(Finish) T (x); //Adjust end pointerfinish++; } Else if(Space_end = =finish) {            //Space Not enough            intOlen = Finish-start; intNlen = Olen = =0?1: Olen *2; T* New_start = (t*) malloc (Nlen *sizeof(T)); T* New_finish =New_start;  for(intI=0; i<olen; i++) {                //copy old data to new space                New(new_finish++) T (* (Start +i)); }            //Append pushed element            New(new_finish++) T (x); //deconstruct Old Ones             for(intI=0; i<olen; i++) {(Start+i)->~T ();                        } free (start); Start=New_start; Finish=New_finish; Space_end= Start +Nlen; } Else {            //State Invalidcerr<<"Error"<<Endl; }    }        ~Myvector () { for(t* S=start; s<finish; s++) {s->~T ();    } free (start); }};#defineuse_org 0intMain () {Long* A =NULL; Long* B = A +1; intn = (Char*) B-(Char*) A; cout<<n<<Endl; intLast_capacity =-1; Object::count=0; #ifuse_orgVector<Object>tmp;#elseMyvector<Object>tmp;#endif     for(intI=0; i<5; i++) {Tmp.push_back (Object (i)); if(Last_capacity! =tmp.capacity ()) {cout<<"======last Cap:"<<last_capacity<<"New Capacity:"<<tmp.capacity () <<Endl; Last_capacity=tmp.capacity (); } cout<<"\ n"<<Endl; } myvector<int>ints; Ints.push_back (2); Ints.push_back (3); Ints.push_back (1);        Sort (Ints.begin (), Ints.end ());  for(inti:ints) {cout<<i<<Endl; } System ("Pause"); return 0;}

C + + Stl:vector implementation