Effective C++ 第3版 Item 26详尽研究 个人认为最后一些内容有待商酌

//Create By 九天雁翎（jtianling） Email:jtianling@gmail.com
//博客：blog.jtianling.cn

#include <vector>
#include <string>
#include "jtianling/jtianling.h"

using namespace std;

void ApproachA1(int n);
void ApproachB1(int n);
void ApproachA2(int n);
void ApproachB2(int n);
void ApproachA3(int n);
void ApproachB3(int n);
void ApproachA4(int n);
void ApproachB4(int n);

int main()
{
    const int n = 8;
    vector<jtianling::pfI> pfIVec;
    pfIVec.push_back(ApproachA1);
    pfIVec.push_back(ApproachB1);
    pfIVec.push_back(ApproachA2);
    pfIVec.push_back(ApproachB2);
    pfIVec.push_back(ApproachA3);
    pfIVec.push_back(ApproachB3);
    pfIVec.push_back(ApproachA4);
    pfIVec.push_back(ApproachB4);
    vector<int> iVec;
    iVec.push_back(10);
    for(int i=0; i<n; ++i)
    {
       iVec.push_back(iVec[i]*5);
    }
    jtianling::CompareAlgorithmI(pfIVec, iVec);
}

//比较int x
void ApproachA1(int n)
{
    int x;
    for(int i=0; i<n; ++i)
    {
       x = i;
    }
}

void ApproachB1(int n)
{
    for(int i=0; i<n; ++i)
    {
       int x = i;
    }
}

//比较string
void ApproachA2(int n)
{
    string s;
    for(int i=0; i<n; ++i)
    {
       s = "good";
    }
}

void ApproachB2(int n)
{
    for(int i=0; i<n; ++i)
    {
       string s("good");
    }
}

//比较vector
void ApproachA3(int n)
{
    vector<int> vec(n);
    vector<int> vec2(n,1);
    for(int i=0; i<n; ++i)
    {
       vec[i] = vec2[i];
    }
}

void ApproachB3(int n)
{
    vector<int> vec2(n,1);     //抵消ApproachA3中的一次建构析构.
    for(int i=0; i<n; ++i)
    {
       vector<int> vec(1,i);
    }
}

void ApproachA4(int n)
{
    int *a = new int[n];
    int *b = new int[n];
    for(int i=0; i<n; ++i)
    {
       b[i] = i;
    }
    for(int i=0; i<n; ++i)
    {
       a[i] = b[i];
    }
    delete a;
    delete b;
}

void ApproachB4(int n)
{
    //以下过程抵消ApproachA4相关过程
    int *b = new int[n];
    for(int i=0; i<n; ++i)
    {
       b[i] = i;
    }
    for(int i=0; i<n; ++i)
    {
       int *a = new int();
       delete a;
    }
    delete b;
}