askvalue(){
echo -n "$1 [$2] : "
read answer
if [ ${answer:=$2} -gt $3 ]; then
echo "$0: $1 $answer is invalid"
exit 0
elif [ "$(( $(echo $answer | wc -c) - 1 ))" -lt $4 ]; then
echo "$0: $1 $answer is too short: please specify $4 digits"
exit 0
fi
eval $1=$answer
}
eval $(date "+nyear=%Y nmon=%m nday=%d nhr=%H nmin=%M")
askvalue year $nyear 3000 4
askvalue month $nmon 12 2
askvalue day $nday 31 2
askvalue hour $nhr 24 2
askvalue minute $nmin 59 2
squished="$year$month$day$hour$minute"
date $squished
exit 0