 

Category: containers   Component type: concept 
Description
A Random Access Container is a ReversibleContainer whose iterator type is a RandomAccessIterator. It provides amortized constant time access to arbitrary elements.
Refinement of
ReversibleContainer
Associated types
No additional types beyond those defined in ReversibleContainer. However, the requirements for the iterator type are strengthened: it must be a RandomAccessIterator.
Notation
X  A type that is a model of Random Access Container 
a , b  Object of type X 
T  The value type of X 
Definitions
Valid expressions
In addition to the expressions defined in ReversibleContainer, the following expressions must be valid.
Name  Expression  Type requirements  Return type 
Element access  a[n]  n is convertible to size_type  reference if a is mutable, const_reference otherwise 
Expression semantics
Semantics of an expression is defined only where it is not defined in ReversibleContainer, or where there is additional information.
Name  Expression  Precondition  Semantics  Postcondition 
Element access  a[n]  0 <= n < a.size()  Returns the n th element from the beginning of the container.  
Complexity guarantees
The runtime complexity of element access is amortized constant time.
Invariants
Element access  The element returned by a[n] is the same as the one obtained by incrementing a.begin() n times and then dereferencing the resulting iterator. 
Models
Notes
See also
The Iterators, RandomAccessIterator, Sequence