Просмотр кода страницы Frequency-ordered binary search tree

'''Frequency-ordered binary search tree''' --- частотно-упорядоченные
бинарные деревья поиска. 

'''Frequency-ordered binary search tree''' (or '''FOBT''') is a binary search
tree that satisfies the condition that the root of a subtree must have
the highest frequency. In other words, the frequencies of nodes along
any path (from root top leaf) must be decreasing (or not-increasing).
It has been shown that the ratio between the access cost of a FOBT and
the optimal tree may be as high as <math>n/(4\log n)</math>.