Write a shell program to find the sum of alternate digits in a given 5-digit number

Hi Can any one please post the answer for the above program..................

banta.sh 28462

banta.sh:

#!/bin/ksh

a="${1}"

typeset -i i=1

while (( i <= 5 ))
do
  ((num=$(echo "${a}" | cut -c "${i}") ))
  if (( i == 1 )); then
     printf "$num"
  else
     printf "+$num"
  fi
  ((sum=sum + num))
  ((i=i+2))
done

printf "=${sum}\n"

Python alternative

#!/usr/bin/python
a = 12345
b = list(str(a))
print sum( map(int,b[::2]) )

output:

9

You need to initialise the variables num and sum

#!/bin/ksh

a=12346
b=`expr length $a`
echo " length : $b"
typeset -i i=1
num=0
sum=0
while (( i <= $b ))
do
((num=$(echo "${a}" | cut -c "${i}") ))
if (( i == 1 )); then
printf "$num"
else
printf "+$num"
fi
((sum=sum + num))
((i=i+2))
done
printf "=${sum}\n"
~

Answer
-------
length : 5
1+3+6=10

Er... obvious example of homework? Thread closed.