7. std::vector access

• Access is limited to the defined range of the vector.

• Otherwise the access is either

  • an exception* thrown by at( ), or

  • undefined with operator[ ].

• operator[ ] can be used on either side of assignment.

  
      const_reference operator[]( size_type pos ) const;
  
      reference operator[]( size_type pos );
  
      const_reference at( size_type pos ) const;
  
      reference at( size_type pos );
  
  

• * if position is out of range, at( ) signals by throwing the out_of_range exception .