Language: Java
The point-region quadtree is a tree-based data structure used to store points in a two-dimensional space.
Language: C
The extensible shell (esh) is a simple shell that provides a Unix-like command line user interface. The esh supports job control, pipes (|), I/O redirection (< > >>), and can run programs that require exclusive access to the terminal (e.g. vim). It also implements the built-in commands ‘jobs,’ ‘fg,’ ‘bg,’ ‘kill,’ and ‘stop,’ along with \ˆC (SIGINT) and \ˆZ (SIGTSTP).
Language: C