Flip-flop, maybe?

perl -le '@full = ( 0..100 );
for ( @full ) {
  print STDOUT "$_: LIGHTS ON" if /20/ .. /30/;
  print STDOUT "$_: LIGHTS OFF" if /60/ .. /70/;
}
'
__output__
20: LIGHTS ON
21: LIGHTS ON
22: LIGHTS ON
23: LIGHTS ON
24: LIGHTS ON
25: LIGHTS ON
26: LIGHTS ON
27: LIGHTS ON
28: LIGHTS ON
29: LIGHTS ON
30: LIGHTS ON
60: LIGHTS OFF
61: LIGHTS OFF
62: LIGHTS OFF
63: LIGHTS OFF
64: LIGHTS OFF
65: LIGHTS OFF
66: LIGHTS OFF
67: LIGHTS OFF
68: LIGHTS OFF
69: LIGHTS OFF
70: LIGHTS OFF
[download]

Though I do not know the proper syntax with variable assignment, so cannot turn the durn lights off! So, it half works....

perl -le '@full = ( 0..20 );
for $ea ( @full ) {
  print STDOUT "$ea: LIGHTS ON" if $ea =~ /6/ .. /10/;
  print STDOUT "$ea: LIGHTS OFF" if $ea =~ /15/ .. /20/;
}
'
__output__
6: LIGHTS ON
7: LIGHTS ON
8: LIGHTS ON
9: LIGHTS ON
10: LIGHTS ON
11: LIGHTS ON
12: LIGHTS ON
13: LIGHTS ON
14: LIGHTS ON
15: LIGHTS ON
15: LIGHTS OFF
16: LIGHTS ON
16: LIGHTS OFF
17: LIGHTS ON
17: LIGHTS OFF
18: LIGHTS ON
18: LIGHTS OFF
19: LIGHTS ON
19: LIGHTS OFF
20: LIGHTS ON
20: LIGHTS OFF
[download]

Hope it helps!