29.1 General Trees . . . . . . . . . . . . . . . . . . . . . .
29.1.1 Implementations . . . . . . . . . . . . . . . . .
29.1.2 Traversals . . . . . . . . . . . . . . . . . . . . .
29.2 Project Integration: Formula Parsing . . . . . . . . .
29.2.1 Formula Tree Traversals and In-order Traversal
29.3 Binary Search Trees: Binary Trees as Maps . . . . . .
29.3.1 Order Analysis . . . . . . . . . . . . . . . . . .
29.3.2 Immutable BSTs