NAME
Algorithm::BinaryIndexedTree - data structure for cumulative frequency tables
SYNOPSIS
use Algorithm::BinaryIndexedTree;
my $BIT = Algorithm::BinaryIndexedTree.new();
$BIT.add(5,10);
$BIT.get(0).say; # 0
$BIT.get(5).say; # 10
$BIT.sum(4).say; # 0
$BIT.sum(5).say; # 10
$BIT.add(0,10);
$BIT.sum(5).say; # 20
DESCRIPTION
Algorithm::BinaryIndexedTree is the data structure for maintainig the cumulative frequencies.
CONSTRUCTOR
new
my $BIT = Algorithm::BinaryIndexedTree.new(%options);
OPTIONS
Sets table size. Default is 1000.
METHODS
add
$BIT.add($index, $value);
Adds given value to the index $index.
sum
my $sum = $BIT.sum($index);
Returns sum of the values of items from index 0 to index $index inclusive.
get
my $value = $BIT.get($index);
Returns the value at index $index.
AUTHOR
titsuki titsuki@cpan.org
COPYRIGHT AND LICENSE
Copyright 2016 titsuki
This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.
The algorithm is from Fenwick, Peter M. "A new data structure for cumulative frequency tables." Software: Practice and Experience 24.3 (1994): 327-336.