我编写了以下函数和一个简单的类,同时试图了解使用向量的工作成本有多高
void gen_random(string & str, const int len)
{
static const char alphanum[] =
"0123456789"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"abcdefghijklmnopqrstuvwxyz";
srand((unsigned int)time(NULL));
str.reserve(len);
for (int i = 0; i < len; ++i)
{
str += alphanum[rand() % (sizeof(alphanum) - 1)];
}
}
class Person
{
public:
//CTOR with parameter
Person(u_int32_t Id)
{
std::cout << "