Shell Programming and Scripting

#!/bin/ksh
read num?"Enter binary 32 bit number: "
set -- $(echo $num | rev | sed 's/./& /g' )
i=0
while [ $i -lt 32 ]
do
   let barray[$i]=${1:-0}
   [ $# -gt 0 ] && shift
   let i=i+1
done
if (( ${barray[0]} ))
then
   echo "barray[0] is 1"
else
   echo "barray[0] is 0"
fi
if (( ${barray[1]} ))
then
   echo "barray[1] is 1"
else
   echo "barray[1] is 0"
fi

$ echo ${.sh.version}
Version M-12/28/93e
$ ./tst
Enter binary 32 bit number: 10101010101010101010101010101010
./tst[12]: typeset: barray: reference variable cannot be an array.