Where am I wrong?

Question

bash

There is such a task:
Look at the function from the bash script:

counter ()  # takes one argument
{
  local let "c1+=$1"
  let "c2+=${1}*2"
}

Enter in the form below the line that the command echo "counters are $c1 and $c2" will display if it is in the script after ten calls to the counter function with parameters first 1, then 2, then 3, etc., the last call with parameter 10.
And now my answer:

for i in {1..10}; do counter $i; echo "counters are $c1 and $c2"; done;

Help, what am I doing wrong?! Or I do not understand .. Thank you.

Answer 1

Enter in the form below the line that the command echo "counters are $c1 and $c2" will display if it is in the script after ten calls to the counter function with parameters first 1, then 2, then 3, etc., the last call with parameter 10.

Or am I wrong?