Problem 6(c)

Please use OCAML

(c) Define a function treeToList (t : a binTree) : (a list) option. If the supplied tree is degenerate, the function should return Some l, where l corresponds to a list constructed by replacing the Node constructors with (::) constructors and replacing the Leaf constructors with the [] constructor where appropriate. If the supplied tree is not degenerate, the function should return None. You are encouraged to use degenerate and foldT to implement this function.