It seems to be taking too much more time comparing to staff's implementation. The other 3 functions are average, though.
dictionary.c: https://gist.github.com/9dcb901f2007d09ae1c9c4fa934f13df
Mine:
WORDS MISSPELLED: 644
WORDS IN DICTIONARY: 143091
WORDS IN TEXT: 19190
TIME IN load: 0.03
TIME IN check: 2.45
TIME IN size: 0.00
TIME IN unload: 0.01
TIME IN TOTAL: 2.50
Staff's:
WORDS MISSPELLED: 644
WORDS IN DICTIONARY: 143091
WORDS IN TEXT: 19190
TIME IN load: 0.04
TIME IN check: 0.02
TIME IN size: 0.00
TIME IN unload: 0.02
TIME IN TOTAL: 0.08