/ 
Binary-Heap-Array-2017.121
River stage zero No dependents
/ Binary::Heap::Array

Name

Binary::Heap::Array - Extensible array each of whose component arrays is an integral power of two wide.

Synopsis

my $a = Binary::Heap::Array::new(ipsw);

$a->push(1)->push(2);
ok $a->size   == 2;
ok $a->at( 0) == 1;
ok $a->at( 1) == 2;
ok $a->at(-1) == 2;
ok $a->at(-2) == 1;
   $a->at( 0)  = 2;
ok $a->at(-2) == 2;
ok $a->pop    == 2;
ok $a->size   == 1;
ok $a->shift  == 2;
ok $a->size   == 0;
$a->unshift(3);
ok $a->size   == 1;
$a->unshift(2);
ok $a->size   == 2;
$a->unshift(1);
ok $a->size   == 3;

Methods

new($flags)

sub new(*) # Create a new binary heap array. A string of flags enables optimizations to the base version, which uses the minimum amount of memory at all times, to use more memory to obtain shorter run times, These flags are: 'i' - retain memory for subsequent reuse rather than freeing it as soon as possible; 'p' - add two fields to each array to optimize shift/unshift operations; 's' - add a field to each array to cache the size of the array; 'w' - add a field each array to cache the current width of the array of subarrays.

   Parameter  Description
1  $flags     Optimization flags ipsw in any order surrounding quotes are not necessary

at :lvalue($array, $index)

Address the element at a specified index so that it can get set or got

   Parameter  Description
1  $array     Array
2  $index     index of element

pop($array)

Pop the topmost element from the leading full array and spread the remainder of its contents as sub arrays of the correct size for each preceding empty slot

   Parameter  Description
1  $array     Array from which an element is to be popped

push($array, $element)

Push a new element on to the top of the array by accumulating the leading full sub arrays in the first empty slot or create a new slot if none already available

   Parameter  Description
1  $array     Array
2  $element   element to push

size($array)

Find the number of elements in the binary heap array

   Parameter  Description
1  $array     Array

shift($array)

Remove and return the current first element of the array

   Parameter  Description
1  $array     Array

unshift($array, $element)

Insert an element at the start of the array

   Parameter  Description
1  $array     Array
2  $element   element to be inserted

Index

"at :lvalue($array, $index)" "new($flags)" "pop($array)" "push($array, $element)" "shift($array)" "size($array)" "unshift($array, $element)"

Installation

This module is written in 100% Pure Perl in a single file and is thus easy to read, modify and install.

Standard Module::Build process for building and installing modules:

perl Build.PL
./Build
./Build test
./Build install

See also

The arrays used to construct the binary heap array are all an integral power of two wide and thus make good use of the memory allocated by Data::Layout::BuddySystem or similar.

Author

philiprbrenan@gmail.com

http://www.appaapps.com

Copyright

Copyright (c) 2017 Philip R Brenan.

This module is free software. It may be used, redistributed and/or modified under the same terms as Perl itself.