/
ch-2.pl
59 lines (50 loc) · 1.38 KB
/
ch-2.pl
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
#!/usr/bin/env perl
use strict;
use warnings;
use experimental qw{ say postderef signatures state };
use List::Util qw{ max sum };
my @examples = (
[ [ 1, 2, 3, 4 ], [ 5, 6, 7, 8 ], [ 9, 10, 11, 12 ] ],
[ [ 1, 0, 0, 0 ], [ 0, 1, 0, 0 ], [ 0, 0, 1, 0 ], [ 0, 0, 0, 1 ] ]
);
for my $e (@examples) {
my $o = submatrix_sum($e);
my $input = format_matrix($e);
my $output = format_matrix($o);
say <<~"END";
Input: \$a = $input
Output: \$b = $output
END
}
sub submatrix_sum ($m) {
my @output;
for my $x ( 0 .. -2 + scalar $m->@* ) {
for my $y ( 0 .. -2 + scalar $m->[$x]->@* ) {
my @z;
push @z, $m->[ $x + 0 ][ $y + 0 ];
push @z, $m->[ $x + 1 ][ $y + 0 ];
push @z, $m->[ $x + 0 ][ $y + 1 ];
push @z, $m->[ $x + 1 ][ $y + 1 ];
my $z = sum @z;
$output[$x][$y] = $z;
}
}
return \@output;
}
sub format_matrix ($matrix) {
my $maxlen = max map { length $_ } map { $_->@* } $matrix->@*;
my $output = join "\n ", '[', (
map { qq{ [$_],} }
map {
join ',',
map { pad( $_, 1 + $maxlen ) }
$_->@*
}
map { $matrix->[$_] } 0 .. -1 + scalar $matrix->@*
),
']';
return $output;
}
sub pad ( $str, $len = 4 ) {
return sprintf "%${len}s", $str;
}