如何打印由另一个字符串链接列表组成的链接列表？

Question

I have decided to use the STL list, although our instructor has been teaching us one that is made from the book. I made this change because the header file from the book is not working with me, most probably my fault. So, after researching online, I have tried my best to understand how the iterator of the STL list works. The following is the code that I made to print the linked list x defined by type list<list<string>> .

  list < list <string>> x;

while (!inData.fail())
{
    //...
    string str(cstr);//cstr at this point is the sorted string
    bool match = false;
    list <string> inner_list;
    inner_list.push_back(str);
    list<list <string>>::const_iterator cit;
    for (cit = x.begin(); !match && cit !=x.end(); advance(cit,1))
    {
        if (*cit == inner_list)
        {
            inner_list.push_back(temp2); //temp2 is unsorted string
            match = true;
        }
    }

    if (match ==false) x.push_back(inner_list);

}

//printing


list<list <string>>::const_iterator it; 
    list<string>::const_iterator it2;
    for (it = x.begin(); it != x.end(); it++)
    {
        for (it2 = it->begin(); it2 != it->end(); it2++)
        {
            cout << *it2 << " ";
        }

    }

I am getting a list iterator dereferencing error, but I have no clue why. I would appreciate any help or hints. And if anything is unclear or needs explanation please tell me.

Answer 1

You can use the following code. Hope this will help you. Thanks.

typedef long long ll;

ll N,M;
string str;
list<string> innerList;
list<list<string> > Data;

cin >> M; // M holds the no. of nodes containing linked list of strings //
for(ll i=0; i<M; i++){
    getchar();
    cin >> N; // No. of strings containing in inner linked list 
    getchar();
    for(ll i=0; i<N; i++){
        cin >> str;
        innerList.push_back(str);
    }

    Data.push_back(innerList);
    innerList.clear();
}

// print data //

for(list<list<string> >::iterator it = Data.begin(); it!=Data.end(); it++){
    for(list<string>::iterator iit = (*it).begin(); iit!=(*it).end(); iit++){
        cout << (*iit) << "  " ;
    }
    cout << "\n";

}