An answer for http://nabetani.sakura.ne.jp/hena/ord28spirwa/

Answer.pm

package Answer;
use strict;
use warnings;
use Exporter qw(import);

our @EXPORT_OK = qw(solve);

sub directions ($$$$$) {
    my ($n, $e, $s, $w, $t) = @_;
    my @directions = (
        [e => $e],
        [s => $t + 1],
        [w => $e],
        [s => $s],
        [w => $t + 1],
        [n => $s],
        [w => $w],
        [n => $t + 1],
        [e => $w],
        [n => $n],
        [e => $t + 1],
        [s => $n - 1],
        [e => 1]
    );
}

sub solve ($) {
    my ($n, $e, $s, $w, $days) = split /[,:]/, $_[0];

    my $t = 1;
    my $d;
    while ($days >= 0) {
        my @directions = directions($n, $e, $s, $w, $t);
        while ($days >= 0 and $d = shift @directions) {
            $days -= $d->[1];
        }
        $t += 2;
    }

    return uc($d->[0]);
}

1;

test.t

use strict;
use warnings;
use Test::More;
use Answer qw(solve);

while (<DATA>) {
    tr/\r\n//d;
    my ($no, $input, $expected) = split /\t/, $_, 4;
    is solve $input, $expected, "test #$no";
}

done_testing;
__END__
0	2,3,5,4:85	S	 
1	1,2,3,4:1	E	 
2	1,2,3,4:2	S	 
3	1,2,3,4:3	S	 
4	1,2,3,4:4	W	 
5	1,2,3,4:27	E	 
6	1,2,3,4:63	E	 
7	1,2,3,4:40	W	 
8	1,4,3,2:40	S	 
9	3,3,3,3:30	S	 
10	3,3,3,3:31	E	 
11	3,3,3,3:32	E	 
12	3,3,3,3:70	S	 
13	3,3,3,3:71	E	 
14	3,3,3,3:72	E	 
15	1,1,1,1:7	N	 
16	1,2,1,1:7	W	 
17	1,6,1,1:7	S	 
18	1,8,1,1:7	E	 
19	1,1,1,1:30	N	 
20	1,2,1,1:30	W	 
21	1,5,1,1:30	S	 
22	1,8,1,1:30	E	 
23	9,9,9,9:99	W	 
24	5,6,3,8:3	E	 
25	5,8,1,1:11	W	 
26	2,8,1,2:18	S	 
27	3,2,3,1:20	N	 
28	3,3,8,1:28	N	 
29	2,5,1,2:32	E	 
30	2,5,1,6:33	E	 
31	1,2,5,7:34	N	 
32	3,6,5,6:36	E	 
33	6,2,8,1:39	S	 
34	3,1,2,3:41	W	 
35	1,1,3,4:45	W	 
36	1,3,1,2:46	N	 
37	4,4,4,4:49	W	 
38	3,1,4,4:55	N	 
39	6,6,2,1:56	W	 
40	3,2,1,2:59	S	 
41	2,7,7,1:60	S	 
42	3,1,1,1:63	N	 
43	4,6,4,1:78	E	 
44	7,5,3,6:79	W	 
45	7,8,3,1:81	E	 
46	3,2,5,2:82	S	 
47	1,1,3,4:84	N	 
48	7,4,1,5:88	S	 
49	3,6,5,3:89	S	 
50	1,4,2,3:92	N	 
51	1,3,4,5:93	W	 
52	2,4,8,1:94	W	 
53	3,6,1,7:99	S	 
54	1234,2345,3456,4567:978593417	E
55	1234,2345,3456,4567:978593418	S
56	31415,92653,58979,32384:9812336139	W
57	31415,92653,58979,32384:9812336140	S
58	314159,265358,979323,84626:89099331642	S
59	314159,265358,979323,84626:89099331643	W