Find whether a tree is a subtree of other

Question

There are two binary trees T1 and T2 which store character data, duplicates allowed.
How can I find whether T2 is a subtree of T1 ? .
T1 has millions of nodes and

Answer 1

Traverse T1. If the current node is equal to the root node of T2, traverse both of the trees (T2 and the current subtree of T1) at the same time. Compare the current node. If they are always equal, T2 is a subtree of T1.