z=0000000000
read
while IFS=. read a b
do
$b$z
$[c+=a,d+=${a//[0-9]}10#${_::10}]
$[s={-,}1,c+=s*=d*s>=(c*s<0?1:1$z),d-=1$z*s]
done
s=$[!c&&d<0?-1:1]
$z${d/-}
echo ${s/1}$c.${_:${#_}-10}