c++ - 在构造函数中初始化 vector C++

Question

我保证我已经四处寻找了很多年的解决方案，但无济于事，但是我没有使用 C++ 的经验，所以也许我只是不知道要搜索什么。

我想最简单的方法是先向您展示我的错误代码，以防它被识别。它有点像一堆东西，这就是为什么我无法理解它以找出问题所在的原因。 (还有为什么我认为这不是我的理解，或者是我犯的一个非常烦人的错误!)

g++ -Wall -pedantic -ansi -std=c++0x -g   -c -o contacts.o contacts.cc
In file included from /usr/include/c++/4.6/vector:63:0,
             from contacts.h:5,
             from contacts.cc:2:
/usr/include/c++/4.6/bits/stl_construct.h: In function ‘void std::_Construct(_T1*,
 _Args&& ...) [with _T1 = person, _Args = {}]’:
/usr/include/c++/4.6/bits/stl_uninitialized.h:481:3:   instantiated from ‘static void
std::__uninitialized_default_n_1<_TrivialValueType>::__uninit_default_n(_ForwardIterator, 
_Size) [with _ForwardIterator = person*, _Size = unsigned int, bool _TrivialValueType = 
false]’
/usr/include/c++/4.6/bits/stl_uninitialized.h:529:7:   instantiated from ‘void 
std::__uninitialized_default_n(_ForwardIterator, _Size) [with _ForwardIterator = 
person*, _Size = unsigned int]’
/usr/include/c++/4.6/bits/stl_uninitialized.h:604:7:   instantiated from ‘void 
std::__uninitialized_default_n_a(_ForwardIterator, _Size, std::allocator<_Tp>&) [with 
_ForwardIterator = person*, _Size = unsigned int, _Tp = person]’
/usr/include/c++/4.6/bits/stl_vector.h:1134:2:   instantiated from ‘void 
std::vector<_Tp, _Alloc>::_M_default_initialize(std::vector<_Tp, _Alloc>::size_type) 
[with _Tp = person, _Alloc = std::allocator<person>, std::vector<_Tp, 
_Alloc>::size_type = unsigned int]’
/usr/include/c++/4.6/bits/stl_vector.h:239:9:   instantiated from ‘std::vector<_Tp, 
_Alloc>::vector(std::vector<_Tp, _Alloc>::size_type) [with _Tp = person, _Alloc = 
std::allocator<person>, std::vector<_Tp, _Alloc>::size_type = unsigned int]’
contacts.cc:7:38:   instantiated from here

编辑:抱歉，我不完全明白我在做什么，但我希望这是你所要求的。如果我的代码中至少有这么多(两个相关文件)，错误仍然会出现:

联系人.h:

#ifndef _CONTACTS_H
#define _CONTACTS_H

#include <iostream>
#include <vector>

#include "person.h"


class contacts{
  private:
  int element;
  int count;
  vector<person> pv;

  public:
  contacts();
};
#endif

和 contacts.cc:

#include "contacts.h"

using namespace std;


contacts::contacts() : count(0), pv(0) {}

谢谢-伊万

Answer 1

为什么要将 0 传递给 std::vector<> 构造函数？这听起来与您所写的效果相同:

联系人::联系人() : count(0) {}