BTree 
Data Structure  BTreeIntroductionBtree is a selfbalancing tree data structure. In a Btree each node may contain a large number of keys and children. The number of children and keys in a Btree is defined by a single numerical parameter  order. Btree is a generalization of 234 tree [3]. Facts about BTree of order K:
BTree of order 5, built from the array of values (7, 16, 1, 2, 5, 6, 12, 9, 21, 18) is shown below. Each node has 9 slots: 5 slots for child references and 4 slots for key values: Key slots contain either a number or when empty an underscore '_' symbol, Reference slots that have link to a child node contain '.' symbol.
ImplementationC# implementation that follows description of Comer's article ^{[1]} is given in two flavors:
Python implementation of 234 tree with add operation
as described in Wikipedia article ^{[3]}:
Open on github
Usage
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