Shell Programming and Scripting

counter=0
sales=0
total=0
echo "enter sales price"
read sales
total=total+sales
while test $sales  ;  do
let "counter=$counter+1"
let "total=$total+$sales"
done
echo $sales
echo $counter
echo $total

while test $sales  ;  do
   let "counter=$counter+1"
   let "total=$total+$sales"
done

counter=0
sales=0
total=0

echo "enter sales price"
read sales

while [ $sales -ne 0 ]  ;  do
   echo "enter sales price \c"  # echo -n with no \c in bash
   read sales
   
   counter=$((counter+1))
   let total=$((total+sales))
done
echo $sales
echo $counter
echo $total

echo "enter sales price"
read sales
. . .
while. . .
echo "enter sales price \c"
read sales