友元类

[oro724]

程序如下,为何编译出错,显示Segmentation Fault (core dumped),请指教
#include <iostream>
using namespace std;

const int len = 10;

class Node
{
public:
friend class Chain;
private:
int date;
char ch[len];
Node* next;
};




class Chain
{
public:
Chain();
~Chain();
void Output(ostream& out)const;
private:
int length;
Node* first;
};

Chain::Chain()
{
length = 0;
first = NULL;
}

Chain::~Chain()
{
Node* link;
while (first)
{
link = first->next;
delete first;
first = link;
}
link = NULL;
}

void Chain::Output(ostream& out)const
{
out << first->date;
}

int main()
{
Chain CS;
CS.Output(cout);

}

[taodm]

VC6？而且没打sp6补丁？

[xkyx_cn]

first->date;
使用NULL指针，内存读写错误，可以加一个判断:

if (NULL != first)
    out << first->date; 

[oro724]

不是
是在unix下的编译器

[oro724]

牛
2楼说的很对
谢谢啊
同时也感谢1楼关注~~

[mimong_lin]

是OUTPUT出错的吗，是的话就如2楼说的那样了；如果不是的话，请贴出是哪个地方出错了。