Selecting size of vector of vectors
<p>I have a class called Grid that declares a vector of vectors like this:</p>

<pre><code>typedef vector&lt;int&gt; row;
typedef vector&lt;row&gt; myMatrix;

myMatrix sudoku_;
</code></pre>

<p>The constructor looks like this:</p>

<pre><code>grid::grid() : sudoku_(9,9)
{

}
</code></pre>

<p>As you can see, the constructor is initializing it to be a 9x9 grid. How can I make it work so that the user is asked for a number, say n, and the grid is initialized n x n ?</p>
