or download this
#!/usr/bin/perl -l
pop=~m|/|;($f,$g)=($`,$');sub d{int($_[1]/$_[0]+1)}sub
...
for($p,$l){$_/=$g};($p,$l)}while($f>1){push@o,"1/".d(#
$f,$g);($f,$g)=re($f,$g,1,d($f,$g));}print join' + ',#
@o,"$f/$g";# ungolfed and thus not for production use!