std:sort和字符串hash函数

class CStudent

{

public:

CStudent() {}

~CStudent() {}

bool operator<(const CStudent &stu) const

{

return num > stu.num;

}

int num;

};

struct cmp
{

bool operator() ( CStudent &a, CStudent &b )

{

return a.num < b.num; 

}

};  

bool rankStudent(const CStudent &stu1, const CStudent &stu2)

{

return stu1.num > stu2.num;

}

int _tmain(int argc, _TCHAR* argv[])

{

vector vec;

for (int i = 0; i < 10; i++)

{

CStudent stu;

stu.num = rand();

vec.push_back(stu);

}

//sort(vec.begin(), vec.end());

sort(vec.begin(), vec.end(), rankStudent);

for (int i = 0; i < 10; i++)

{

cout<

}

        priority_queue,cmp*/> tmpQueue;

for (int i = 0; i < 10; i++)

{

CStudent stu;

stu.num = rand();

tmpQueue.push(stu);

}

while(!tmpQueue.empty())

{

CStudent &stu = tmpQueue.top();

cout<

tmpQueue.pop();

}

getchar();

return 0;

}

unsigned long long hashCode(std::string str) 

{

unsigned long long ulRet = 0;

for (unsigned int i = 0; i < str.size(); i++)

{

ulRet = 31 * ulRet + str[i];

}

return ulRet;

}