#/usr/bin/perl
$nx=10;
$ny=5;

$initialisation = 0;

foreach $i (0..$nx) {
   foreach $j (0..$ny) {
      $a[$i][$j] = $initialisation;
   }
}

$a[1][1] = 2;

&subro($nx,\@a,$ny);

sub subro($nx,\@a,$ny) {

my $nx = shift;
my @a = @{shift}; #should be wrong...
my $ny = shift;

print "$a[1][1]\n";
print "$nx\n";
print "$ny\n";

}