
Data Structure

This illustrates a data structure, a means of storing data within a program.

You may see other such structures in the Data Structures category.
 Illustration of FIFO behavior
Task

Implement a FIFO queue.

Elements are added at one side and popped from the other in the order of insertion.



Operations:

   push   (aka enqueue)    - add element
   pop     (aka dequeue)    - pop first element
   empty                             - return truth value when empty


Errors:

   handle the error of trying to pop from an empty queue (behavior depends on the language and platform)


See

   Queue/Usage   for the built-in FIFO or queue of your language or standard library.


See also

 Array
 Associative array: Creation, Iteration
 Collections
 Compound data type
 Doubly-linked list: Definition, Element definition, Element insertion, List Traversal, Element Removal
 Linked list
 Queue: Definition, Usage
 Set
 Singly-linked list: Element definition, Element insertion, List Traversal, Element Removal
 Stack


 
set myFoods to be an empty list
 
push "grapes" into myFoods
push "orange" into myFoods
push "apricot" into myFoods
 
put "The foods in my queue are: " & myFoods
 
pull from myFoods into firstThingToEat
 
put "The first thing to eat is: " & firstThingToEat
 
if myFoods is empty then
    put "The foods list is empty!"
else
    put "The remaining foods are: " & myFoods
end if
 