Judy is a C library that provides a state-of-the-art core technology that
implements a sparse dynamic array. Judy arrays are declared simply with a null
pointer. A Judy array consumes memory only when it is populated, yet can grow
to take advantage of all available memory if desired. Judy's key benefits are
scalability, high performance, and memory efficiency. A Judy array is
extensible and can scale up to a very large number of elements, bounded only by
machine memory. Since Judy is designed as an unbounded array, the size of a
Judy array is not pre-allocated but grows and shrinks dynamically with the
array population.
