DIR="/Users/Natalie/1/kuku.txt"
n="Users/Natalie/1/$kuku.txt"
#echo "${n:0:4} ${n:4:2} ${n:6:2} ${n:8:2}"

fourthoct=${n:0:4}
thirdoct=${n:4:2}
secondoct=${n:6:2}
firstoct=${n:8:2}

if [ "$(ls -A $DIR)" ] then
sort /Users/Natalie/1/kuku.txt | tail -1 |

     while read firstoct secondoct thirdoct fourthoct
               do
            if [ $((++firstoct)) -eq 101 ]
                   then

                  firstoct=0
                   if [ $((++secondoct)) -eq 32 ]
                        then
 secondoct=0
                         if [ $((++thirdoct)) -eq 13 ]
                               then
                                thirdoct=0
                                   ((++fourthoct))
fi
fi
fi

echo $fourthoct$thirdoct$secondoct$firstoct >kuku.txt
done
else
echo "Hi its new file" >kuku.txt
fi