#!/usr/bin/perl

my $n = 2;
my $max_exp = 1;

use strict;

my $max_part = 2**$max_exp;

my $size = 2**$n;

print "Matrix is $size by $size.\n";
print "Max size I'm allowed to print is $max_part at a time.\n";

my $max_part_tiles = $max_part**2;

my $total_tiles = ($size)**2;
my $tiles_counted = 0;
my $part_tiles_counted = 0;

my ($row_num, $col_num, $end_col) = (0, 0);
my ($cols_displayed, $rows_displayed) = (0, 0);

while($tiles_counted < $total_tiles){

        $col_num=0;
        $end_col=$max_part;
        while($row_num < $size){
                while($col_num < $end_col){
                        print "$row_num $col_num\n";
                        $col_num++;
                        $part_tiles_counted++;
                }
                if($col_num < ($size-1) && (($row_num + 1) % $size > 0) ){
                        $row_num++;
                        $col_num-=$max_part;
                }
                if($col_num < ($max_part-1) && $row_num == ($size-1)){
                        # $col_num++;
                        $row_num-=$max_part;
                        $end_col+=$max_part;
                }
                if($col_num == ($size-1) && $row_num < ($size-1)){
                        $row_num++;
                        $col_num-=$max_part;
                }
                if($col_num == ($max_part-1) && $row_num == ($size-1)){
                        $row_num++;
                        $col_num=0;
                        $end_col=$max_part;
                }
                $tiles_counted += $part_tiles_counted;
        }

}