In computer science, an AVL tree is a self-balancing binary search tree, and it was the first such data structure to be invented.

In an AVL tree, the heights of the two child subtrees of any node differ by at most one.

In other words AVL tree is a binary search tree where the height of the left subtree differs from the height of the right subtree by at most 1 level, if it exceeds 1 level then rebalancing occurs.

The AVL tree is named after its two Soviet inventors, G. M. Adelson-Velskii and E. M. Landis, who published it in their 1962 paper " An algorithm for the organization of information.

Basic operations of an AVL tree involve carrying out the same actions as would be carried out on an unbalanced binary search tree, but modifications are preceded or followed by one or more operations called tree rotations, which help to restore the height balance of the subtrees.

Lookup in an AVL tree is performed exactly like in any unbalanced binary search tree.

* Self balancing AVL tree with Concat and Split operations

The AVL tree is another structure supporting O ( log n ) search, insertion, and removal.

Tree rotations are used in a number of tree data structures such as AVL trees, red-black trees, splay trees, and treaps.

Pictorial description of how rotations cause rebalancing in an AVL tree.

A type of tree which uses this rebalancing technique is the AVL tree.

* AVL tree, red-black tree, and splay tree, kinds of binary search tree data structures that use rotations to maintain balance.

** AVL tree

* AVL tree, a data structure used in computer programming

* AVL tree

# Asheville, NC ( AVL ) – Asheville Regional Airport

Using an AVL system allows to evaluate the locations of all vehicles in service with driver and other crew in order to pick the vehicle that will most likely arrive at the destination fastest, ( meeting the service objective ).

AVL trees are often compared with red-black trees because they support the same set of operations and because red-black trees also take O ( log n ) time for the basic operations.

* 1964 – Prometheus, a bristlecone pine and the world's oldest tree, is cut down.

* Semantic analysis ( computer science ) – a pass by a compiler that adds semantical information to the parse tree and performs certain checks

* 1964 – Prometheus, a bristlecone pine and the world's oldest tree, is cut down.

Since 1977, New Zealand has celebrated Arbor Day on June 5, which is also World Environment Day, prior to then Arbor Day, in New Zealand, was celebrated on August 4 – which is rather late in the year for tree planting in New Zealand hence the date change.

* family of Gediminas – family tree of Aldona

What makes an individual substance – a man, a tree, a planet – real is a distinct act, a " to be ", which actuates its unity.

Many species of neornithines can build burrows, or nest in tree holes or termite nests, all of which provided shelter from the environmental effects at the K – T boundary.

* 1935 – Pravda publishes a letter by Pavel Postyshev, who revives New Year tree tradition in the Soviet Union.

Since 1993, the Eritrean People ’ s Liberation Front army has been involved in tree planting ; the annual average rate of deforestation during 1990 – 2000 was 0. 3 percent.

:* Random fractals – use stochastic rules ; e. g., Lévy flight, percolation clusters, self avoiding walks, fractal landscapes, trajectories of Brownian motion and the Brownian tree ( i. e., dendritic fractals generated by modeling diffusion-limited aggregation or reaction-limited aggregation clusters ).

# Sparse trees and parkland – Natural forests in which the tree canopy cover is between 10 – 30 %, such as in the steppe regions of the world.

# Mangroves – Natural forests with > 30 % canopy cover, composed of species of mangrove tree, generally along coasts in or near brackish or seawater.

# Sparse trees and parkland – Natural forests in which the tree canopy cover is between 10 – 30 %, such as in the savannah regions of the world.

The family tree of Louis III, Duke of Württemberg | Ludwig Herzog von Württemberg ( ruled 1568 – 1593 )

they excavate a nest in a dead or partially dead tree about 8 – 15m from the ground before they have their young.

The tree grows to 60 – 70 m ( 200 – 230 ft ) tall and has a very substantial trunk up to 3 m ( 10 ft ) in diameter with buttresses.

By the end of the Cretaceous, angiosperms dominated tree floras in many areas, although some evidence suggests that biomass was still dominated by cycad and ferns until after the Cretaceous – Paleogene extinction.

The leafy branches of the olive tree – the olive branch as a symbol of abundance, glory and peace – were used to crown the victors of friendly games and bloody wars.

The Prophet Mohamed is reported to have said: " Take oil of olive and massage with it – it is a blessed tree " ( Sunan al-Darimi, 69: 103 ).

Often one floodlight high in a tree will provide all the light you need at much less expense.

Proclamation No. 396 enjoined the " active participation of all government agencies, including government-owned and controlled corporations, private sector, schools, civil society groups and the citizenry in tree planting activity and declaring June 25, 2003 as Philippines Arbor Day.

Lookup, insertion, and deletion all take O ( log n ) time in both the average and worst cases, where n is the number of nodes in the tree prior to the operation.

However, exploring all n nodes of the tree in this manner would use each link exactly twice: one traversal to enter the subtree rooted at that node, and another to leave that node's subtree after having explored it.

However, the nickname is also factually accurate, as the city ’ s tree coverage percentage is at 36 %, the highest out of all major American cities, and above the national average of 27 %.

Outside the tree, there is often a reference to the " root " node ( the ancestor of all nodes ), if it exists.

The set of all nodes at a given depth is sometimes called a level of the tree.

* A perfect binary tree is a full binary tree in which all leaves are at the same depth or same level, and in which every parent has two children.

* A complete binary tree is a binary tree in which every level, except possibly the last, is completely filled, and all nodes are as far left as possible.

However, the tree constructed by the living tree project, a collaboration between ARB-Silva and LPSN where a 16S ( and 23S if available ) tree of all validated species was constructed, the genus Bacillus contains a very large number of nested taxa and majorly in both 16S and 23S it is paraphyletic to Lactobacillales ( Lactobacillus, Streptococcus, Staphylococcus, Listeria, etc.

Rock, ice and tree climbing all usually use ropes for safety or aid.

To handle a molecule containing one or more cycles, one must first expand it into a tree ( called a hierarchical digraph by the authors ) by traversing bonds in all possible paths starting at the stereocenter.

A clade ( from Ancient Greek, klados, " branch ") or monophylum ( see monophyletic ) is a group consisting of an ancestor and all its descendants, a single " branch " on the " tree of life ".

A common convention is to have a < tt > cgi-bin /</ tt > directory at the base of the directory tree and treat all executable files within it as CGI scripts.

Node-based compositing represents an entire composite as a tree graph, linking media objects and effects in a procedural map, intuitively laying out the progression from source input to final output, and is in fact the way all compositing applications internally handle composites.

also written von Haeckel, was an eminent German biologist, naturalist, philosopher, physician, professor and artist who discovered, described and named thousands of new species, mapped a genealogical tree relating all life forms, and coined many terms in biology, including anthropogeny, ecology, phylum, phylogeny, stem cell, and the kingdom Protista.

*“ Be religiously careful in our choice of all public officers ... and judge of the tree by its fruits .”

found in all regions capable of sustaining tree growth, at altitudes up to the tree line, except where natural fire frequency or other disturbance is too high, or where the environment has been altered by human activity.