Monks,

Being new with Perl I am stumbling about in confusion. I am attempting to write a simple calculator which takes the elements from a user entered array (consisting of more than 2 elements), then adds, subtracts, etc.. the elements.

The problem I am having is how to keep a running result of the subtraction value. I only know how to subtract single elements such as: 
$c = $a - $b;

[download]
What I am looking to do is get a final subtracted value. This is where I have stalled:
... code ...
sub subtraction{
  chomp(@_ = split(" ", <STDIN>)); # user enters values on one line
  foreach(@_) {
    $result -= $_;    # I guess I am using the WRONG operator
  }
print "Result: $result\n\n";
... rest of subroutine code ...
}

[download]
So if the array was 4 3 1, the result would be (4 - 3 - 1) = 0

Your help has always been timely and invaluable in the past. Any hints as to the proper way to implement this code are very appreciated since I plan to extrapolate (if possible) your aid into the multiplication and division components of this script. Thank you.

In reply to simple math by paurus

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