use English;
sub doesntchangefirst1{my $first = $ARG[0]; $first = 99;}

# The following causes a compiler error:
sub doesntchangefirst2{my $first = shift @ARG; $first = 99;}

# The one above should be like this:
sub doesntchangefirst3{my $first = shift @ARG; $first = 99;}

sub doesntchangefirst4{my $first = shift ; $first = 99;}

@a = (1,2,3,4);

print @a, "\n";

doesntchangefirst1 @a; print @a, "\n";
doesntchangefirst2 @a;print @a, "\n";
doesntchangefirst3 @a;print @a, "\n";
doesntchangefirst4 @a;print @a, "\n";


$i = shift @a;

print $i, "\n";
print @a, "\n";

sub returnFirstTwoRev{
    my ($first, $second) = @ARG;
    return ($second, $first);
}

@a = (11..15);

@l = returnFirstTwoRev @a;  # Prints 21

print join (",", @l), "\n";

$x = returnFirstTwoRev @a;  # Prints 21

print $x;