my @a = (1,23,451,289,5); my @b = (341,561,5,67,78,891); &func( \@a); &func (\@b); sub func(){ my @myarray = @{$_[0]}; my $max; my $index; my $x = 0; for ( @myarray ) { if (!defined $max or $_ > $max ){ $index = $x ; $max = $_; } $x++; } print "The greatest is element number $index: $myarray[$index]\n"; }