delete class GT
Merge branch 'prim'
changed file names
changed file name
Merge branch 'master' of github.com:yutingyw/jee-yuting-exercise

* 'master' of github.com:yutingyw/jee-yuting-exercise:
  changed file name
  changed file names
  delete class GT
Merge branch 'master' of github.com:jeeyoungk/jee-yuting-exercise

* 'master' of github.com:jeeyoungk/jee-yuting-exercise:
  Minor style fixup in ywprim.py