What is an Iterator class?
- 1 Answers
- 787 Views
- I also Faced
- E-Mail Answers
Answer / ritesh pal
A class that is used to traverse through the objects maintained by a container class. There are five categories of iterators:
input iterators,
output iterators,
forward iterators,
bidirectional iterators,
random access.
An iterator is an entity that gives access to the contents of a container object without violating encapsulation constraints. Access to the contents is granted on a one-at-a-time basis in order. The order can be storage order (as in lists and queues) or some arbitrary order (as in array indices) or according to some ordering relation (as in an ordered binary tree). The iterator is a construct, which provides an interface that, when called, yields either the next element in the container, or some value denoting the fact that there are no more elements to examine. Iterators hide the details of access to and update of the elements of a container class.
The simplest and safest iterators are those that permit read-only access to the contents of a container class. The following code fragment shows how an iterator might appear in code:
cont_iter:=new cont_iterator();
x:=cont_iter.next();
while x/=none do
...
s(x);
...
x:=cont_iter.next();
end;
In this example, cont_iter is the name of the iterator. It is created on the first line by instantiation of cont_iterator class, an iterator class defined to iterate over some container class, cont. Succesive elements from the container are carried to x. The loop terminates when x is bound to some empty value. (Here, none)In the middle of the loop, there is s(x) an operation on x, the current element from the container. The next element of the container is obtained at the bottom of the loop.
| Is This Answer Correct ? | 0 Yes | 0 No |
Specify different types of decision control statements?
How should a contructor handle a failure?
What is a float in c++?
What is runtime errors c++?
template<class T, class X> class Obj { T my_t; X my_x; public: Obj(T t, X x) : my_t(t), my_x(x) { } }; Referring to the sample code above, which one of the following is a valid conversion operator for the type T? a) T operator T () { return my_t; } b) T operator(T) const { return my_t; } c) operator(T) { return my_t; } d) T operator T (const Obj &obj) { return obj.my_t; } e) operator T () const { return my_t; }
What are its advantages and disadvantages of multiple inheritances (virtual inheritance)?
Difference between strdup and strcpy?
What are libraries in c++?
What is a pointer how and when is it used?
What is c++ redistributable?
What is a parameterized type?
How to implement is-a and has-a class relationships?
STL 
