Test if tree is Binary Search tree
30954
How do you validate a binary search tree?
137090
Check if a Class Object is subclass of another Class Object in Java
96459
Check if instance is of a type
38241
How do I check for nulls in an '==' operator overload without infinite recursion?
44454
Rooted Binary Trees and Catalan Numbers
88014
Binary search (bisection) in Python
37773
How do I detect whether a Python variable is a function?
103811
Can I determine if an argument is string literal?
98143
How To Detect If Type is Another Generic Type
157088
What is return type of `if` statement
28580
Is there a module for balanced binary tree in Python's standard library?
119425
TreeForm and Unevaluated
98222
Testing pointers for validity (C/C++)
13767
Number of nodes in binary tree given number of leaves
124040
Testing if a hash has any of a number of keys
126785
How can rooted and unrooted (phylogenetic) trees be distinguished from one another
155463
How Do I Choose Between a Hash Table and a Trie (Prefix Tree)?