title: Multi-dimensional vector
body: <p>How can I create a 2D vector? I know that in 2D array, I can express it like:</p>
  
  <pre><code>a[0][1]=98;
  a[0][2]=95;
  a[0][3]=99;
  a[0][4]=910;
  
  a[1][0]=98;
  a[1][1]=989;
  a[1][2]=981;
  a[1][3]=987;
  </code></pre>
  
  <p>How can one do this using the C++ STL Vector?</p>