vector of 2d array elements?

Hello,

I want to make a vector of 2d arrays. How do I do that. I tried different things... like

Code:

---

vector <char *> vector_x;
vector_x.pushback(new char[13][2]);

---

but that did not work.

Also, how would specific elements be utilized? For the code above I tried using:

Code:

---

b_file>>*vector_x[index_i][index_y][0];

---

I hope my n00bness does not make you laugh too hard.

thanks
J

You need to use a double pointer, as I call it, or a pointer to a pointer. However I would much rather use a vector of a vector of a string. Pretty much the same job but much simpler.

Code:

---

std::vector<char**> vector_x;
std::vector<std::vector<std::string> > vector_y;

---

Desolation,

Thank for the help.

The pushback did not work though. Got the same compiler error. Here is the actual code I am using.

Code:

---

vector <char **> HAND;
while (!b_file.eof())
                {
                HAND.push_back(new char[13][2]);

---

Desolation,

Another question. For your vector of a vector suggestion, how would I utilize it, e.g. how would I store a string?

It depends on what you're trying to do. Here's one example.

Code:

---

vector<vector<string> > HAND;
string word1;
string word2;
while (b_file >> word1 >> word2)
{
  vector<string> item;
  item.push_back(word1);
  item.push_back(word2);
  HAND.push_back(item);
}

---

Notice how I removed the eof() check in your code. That is generally bad practice and will often lead to incorrect input. If you're using operator>> or getline you can put that call inside the while control instead.

1. Can you be more precise than "doesn't work" because that doesn't mean anything to me. You're lucky that I know the answer though. You need to do something like this:

Code:

---

std::vector<char**> HAND;
while(!b_file.eof() )
{
    char** tmp = new char*[13];
    for(int i = 0; i < 13; i++)
        tmp[i] = new char[2];
    HAND.push_back(tmp);
}

---

Of course, you need to delete all those arrays somewhere in your application as well.

Code:

---

std::vector< std::vector< std::string > > HAND;
while (!b_file.eof())
{
    HAND.push_back(std::vector< std::string > ( ));
    // HAND.back().push_back("foo")
}

---

Added that comment bit so you can see how to add a string but you don't need to initialize memory or whatever. =)

Thank you very much for all the information. You are a gentleman and a scholar.