\newcount\m  % ºÐÀÚ
\newcount\n  % ºÐ¸ð 
\newcount\t  % t = m % n
\newcount\s  % s = m / n

\def\cf#1#2{\m=#1 \n=#2 \t=\m
  \divide\m by\n \s=\m \multiply\m by\n \advance\t by-\m
  \number\s \ifnum\t>0+{\strut1\hfill\over\displaystyle\cf\n\t}\fi}

\def\cfrac#1#2{{#1\over#2}=\cf{#1}{#2}}