chdir "/home/www";
opendir DIR, ".";
my @third_level_dirs =
    (
     # 3. This tests for their presence
     grep { -d }
        (
         # 2. This adds /logs to the end
         map { "$_/logs" }
             (
              # 1. this returns all directories but . & ..
              grep { !/^\.\.?$/ && -d } (readdir DIR)
             )
        )
    );
closedir DIR;