title: Pointer to an Element of a Vector
body: <p>If I have a pointer that is pointing to an element in a vector, say element 2, and then that element gets swapped with element 4 of the same vector.  Is the pointer now pointing to element 2, element 4, or neither?  Example:</p>
  
  <p>vector a is equal to [1,2,3,4,5]<br>
  create pointer that points to the element 2, which is equal to 3 in this case<br>
  swap elements 2 and 4<br>
  vector a is now [1,2,5,4,3]  </p>
  
  <p>where is the vector pointing to?</p>