Shell Programming and Scripting

#!/bin/ksh

if [ "$1" -ge "1" -a "$1" -le "24" ]; then
  echo "Okay"
else
  echo "No way"
fi

exit 0

#!/bin/ksh

echo "$1" | egrep '(0[1-9]|1[0-9]|2[0-4])' >/dev/null 2>&1

if [ "$?" -eq "0" ]; then
  echo "Okay"
else
  echo "No way"
fi

exit 0

case $REPLY in
    0[1-9]|1[0-9]|2[0-4]) echo ok ;;
    *) echo not ;; 
esac

#!/bin/ksh

typeset -RZ2 NUM=$1

if [ "$NUM" -ge "1" -a "$NUM" -le "24" ]; then
  echo "Okay"
else
  echo "No way"
fi