# A counting function for trees and lists of trees.

We define a type of trees based on lists of trees. In this type, an
node can have an arbitrary (but finite) number of children, grouped in a list.

Require Export List.
Inductive ltree (A:Set) : Set :=
lnode : A -> list (ltree A)-> ltree A.

For this type, define a function `count`
that counts the number of nodes in a tree.

## Solution

Look at this file

Going home

Pierre Castéran