Problem sets are provided with only an API, and sometimes a test client, but no skeleton code.

Many thanks to Robert Sedgewick, Kevin Wayne, Princeton and Coursera for providing such an outstanding learning experience.

Percolation

Determines whether an n x n grid percolates (ie, whether a cell at the top is connected with a bottom cell), using a weighted quick union-find algorithm.

Queues

Standard implementation of a deque and a randomized queue.

Collinear Points

Finds all set of four or more collinear points in a plane. Brute-force and fast approaches.

8-Puzzle

Solves an 8-puzzle (and n x n generalizations) using an A* algorithm.

Kd-Tree

Find all points within a rectangle in a plane (range-searching) as well as the nearest neighbor to a given point. Brute-force implementation, then fast implementation using a 2D-tree.