Reference
C Library
IOstream Library
Strings library
STL Containers
STL Algorithms
Miscellaneous
STL Containers
bitset
deque
list
map
multimap
multiset
priority_queue
queue
set
stack
vector
deque
comparison operators
deque::deque
deque::~deque
member functions:
deque::assign
deque::at
deque::back
deque::begin
deque::clear
deque::empty
deque::end
deque::erase
deque::front
deque::get_allocator
deque::insert
deque::max_size
deque::operator=
deque::operator[]
deque::pop_back
deque::pop_front
deque::push_back
deque::push_front
deque::rbegin
deque::rend
deque::resize
deque::size
deque::swap


deque::operator[]

public member function
      reference operator[] ( size_type n );
const_reference operator[] ( size_type n ) const;

Access element

Returns a reference to the element at position n in the deque container.

A similar member function, deque::at, has the same behavior as this operator function, except that deque::at signals if the requested position is out of range by throwing an exception.

Parameters

n
Position of an element in the container.
Notice that the first element has a position of 0, not 1.
Member type size_type is an unsigned integral type.

Return value

The element at the specified position in the deque container.

Member types reference and const_reference are the reference types to the elements of the deque container (generally defined as T& and const T& respectively in most storage allocation models).

Example

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// deque::operator[]
#include <iostream>
#include <deque>
using namespace std;
int main ()
{
  deque<int> mydeque (10);   // 10 zero-initialized elements
  unsigned int i;
  deque<int>::size_type sz = mydeque.size();
  // assign some values:
  for (i=0; i<sz; i++) mydeque[i]=i;
  // reverse order of elements using operator[]:
  for (i=0; i<sz/2; i++)
  {
    int temp;
    temp = mydeque[sz-1-i];
    mydeque[sz-1-i]=mydeque[i];
    mydeque[i]=temp;
  }
  cout << "mydeque contains:";
  for (i=0; i<sz; i++)
    cout << " " << mydeque[i];
  cout << endl;
  return 0;
}


Output:
mydeque contains: 9 8 7 6 5 4 3 2 1 0

Complexity

Constant.

See also