Definition
![](images/abi.png)
Special classes:
1) STRICT BINARY TREES are binary trees where every vertex has either 0 or 2 offspring.2) FULL BINARY TREES are binary trees that have 2^k-1 vertices arranged on levels 0,1, ...,k-1, such that on each level i there are 2^i vertices.
3) COMPLETE BINARY TREES are binary trees obtained from a full binary tree by right-to-left elimination of nodes on the last level.
G is minimally connected (if we suppress an edge, the resulting graph is disconnected)