# floor1.txt
# This files contains info about floor 1.

# floor2.txt
# This files contains info about floor 2.

# floor3.txt
# This files contains info about floor 3.

use strict;
use warnings;

my @buildings = qw(building1 building2);
my @floors = qw(floor1 floor2 floor3);
my $current_building;
my $floorfile;

foreach (@buildings)
  {
  $current_building = $_;
  print "$current_building\n\n";
  foreach (@floors)
    {
    $floorfile = $_ . ".txt";
    print "$_\n";
# Why does the while loop, below, mess up the 2nd iteration of the foreach?
#    open FLOORFILE, $floorfile or die $!;
#    while (<FLOORFILE>) 
#      {
#      print "$_\n";
#      }
    }
  print "\n\n"; 
  }