ls |
while read yymm
do
	ls $yymm | grep -v '^'$yymm |
	while read file
	do
		ym=`echo $file|sed 's/^\(....\).*/\1/'`
		if [ ! -d $ym ]
		then
			echo mkdir $ym
			mkdir $ym
		fi
		echo mv $yymm/$file $ym
		mv $yymm/$file $ym
	done
done
