SO - Bash Script Test #1

#! /bin/sh

if [ $# -lt 3 ]
then
    echo "Usage: $0 <file> <digit> <...>"
    exit
fi

if [ $2 -lt 0 -o $2 -gt 9 ]
then
    echo "Second argument must be a digit."
    exit
fi

k=0
s=0

for n in "${@:2}"
do
    if [ $(($n % 10)) -eq $2 ]
    then
        echo "$n are uc $2"

        k=$(($k + 1))
        s=$(($s + $n))
    fi
done

aux=$s
c=0

while [ $aux -gt 0 ]
do
    aux=$(($aux/10))
    c=$(($c+1))
done

if [ -f $1 ]
then
    echo "Suma este $s si are $c cifre" > $1
else
    echo "$1 is not a regular file"
fi