$/*$

$*$ isAsciiDigit $-$ return $1$ if $0$x$30<=$ x $<=0$x$39($ASCII codes for characters $\text{'}0\text{'}$ to $\text{'}9\text{'})$

$*$ Example: isAsciiDigit$(0$x$35)=1.$

$*$ isAsciiDigit$(0$x$3$a$)=0.$

$*$ isAsciiDigit$(0$x$05)=0.$

$*$ Legal ops: $!$ ~ & $^|+<<>>$

$*$ Max ops: $15$

$*$ Rating: $3$

$*/$