SHELL SCRIPT TO CALCULATE SUM OF DIGITS OF A GIVEN NUMBER

SOURCE CODE

echo "Enter the number"
read n
s =0
while ( $n -ne 0 )
do
r =`expr $n % 10`
s =`expr $s + $r`
n =`expr $n / 10`
done
echo "Result= "$s




Output ->  Enter the number
                    123
                   Result= 6