#!/usr/bin/perl
use warnings;
use strict;

#prototyped to explicitly state acceptable arguments

sub addstuff($$$);

my $D=4;
my $E=3;
my $F=2;

#gives error if too few or too many arguments
#(or arguements of wrong type)

my $result = addstuff $D, $E, $F;

print $result."\n";

#prototyped to match

sub addstuff($$$){
        my $A=shift;
        my $B=shift;
        my $C=shift;
        return $A+$B+$C;
}