A Tiny Static Library Model

Model what ar does: bundle object files. Implement: ``c /* archive ops: 0 = add object, 1 = remove object, 2 = link whole archive. objects are named 'a'..'z' characters; adding an existing name replaces it. */ int archive_run(const char *ops); ` archive_run processes ops left to right and returns the number of distinct objects the archive would contain when a link (2`) is hit — or -1 if a link op occurs before any object was added. Duplicates via re-add do not increase the count. Ops are separated by nothing ('a' then 'b' then '2').

Difficulty: intermediate