T1 and T2 are two very large binary trees, with T1 much bigger than T2. Create an algorithm to determine if T2 is a subtree of T1. A tree T2 is a subtree of T1 if there exists a node n in T1 such that the subtree of n is identical to T2.
O(n + km), k is subtree root, m is subtree size
Run make to build and run Swift files. Or you can run .playground file.