I have a list of hours I basically want to subtract 5 from. Why does this code not print the hour "1"? 
#!/usr/bin/perl

use Modern::Perl;

my @f = qw(9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 0 1 2 3 4 5 7 8
+);
foreach my $f (@f){
    my $x = ($f-5)%24;
    say $x;
}

[download]
Why does it output 23 hours: 
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
0
2
3

[download]
And not 24? Where's the 1????? Or at least a blank newline?

In reply to Convet UTC to Eastern Time Zone by Anonymous Monk

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