STL与泛型编程-练习2-GeekBand

练习题目:

struct Programmer{

    Programmer(const int id, const std::wstring name):

         Id(id), Name(name){  }

    void Print() const

    {

        std::wcout<<L"["<<Id<<L"]: "<<Name<<std::endl;

    }

    int Id;

    std::wstring Name;

};

//2, 定义仿函数

//a, 使用ID升序排序

struct ProgrammerIdGreater : public std::binary_function< Programmer, Programmer, bool>{

    bool operator() (const Programmer& p1, const Programmer& p2) const {

    return (key1 <= key2) ? false : true;

    }

};

//b, 使用Name来进行排序

struct ProgrammerNameComparer : public std::binary_function< Programmer, Programmer, bool>{

    bool operator() (const Programmer& p1, const Programmer& p2) const {

    return (p1.GetId() <= p2.GetId()) ? false : true;

    }

};

void main()

{

    //构建数组

    Programmer vp[6] = {

        Programmer("Andrei", 6),

        Programmer("Stanley", 5),

        Programmer("Plaught", 4),

        Programmer("BillGates", 3),

        Programmer("Fowler", 2),

        Programmer("Meyes", 1)

    };

    //构建set

    std::set<Programmer, ProgrammerIdGreater > dest(vp, vp+6);

    //遍历set

    std::for_each( dest.begin(), dest.end(), std::mem_fun(&Programmer::Print) );

    //将dest中的BillGates改为David

    std::set<Programmer, ProgrammerIdGreater>::iterator it = dest.find(Programmer("BillGates", 3));

    if(it != dest.end())

        const_cast<Programmer&>(*it).SetName("David");

    //遍历set

    std::for_each( dest.begin(), dest.end(), std::mem_fun(&Programmer::Print) );

    //新set2用名字排序

    std::set<Programmer, ProgrammerNameComparer > dest2(dest, dest+6);

    //遍历set2

    std::for_each( dest2.begin(), dest2.end(), std::mem_fun(&Programmer::Print) );

}