#!/usr/bin/perl
$\ = "\n";
@y[3,5] = (13,15);
@x = x(@y);

print '@y = (',join (',', map {"'$_'"} @y),')';
print '@x = (',join (',', map {"'$_'"} @x),')';

sub x {
    $_++ for @_;
    @_[1,4] = (2,5);
    &z;
}
sub z {
    $_ *= 3 for @_;
    @_;
}
__END__
@y = ('','','','42','','48')
@x = ('3','6','3','42','15','48')