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
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
|
package PWC253;
/**
* PL/Java implementation for PWC 253
* Task 2
* See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-253>
*
* To install into PostgreSQL execute:
select sqlj.install_jar( 'file:///tmp/PWC253.1.jar', 'PWC253', true );
select sqlj.set_classpath( 'public', 'PWC253' );
select task$tn_pljava();
*/
import org.postgresql.pljava.*;
import org.postgresql.pljava.annotation.Function;
import static org.postgresql.pljava.annotation.Function.Effects.IMMUTABLE;
import static org.postgresql.pljava.annotation.Function.OnNullInput.RETURNS_NULL;
import java.util.*;
/*
example of invocation
java=# select task2_pljava( 4 , array[
[1, 0, 0, 0],
[1, 1, 1, 1],
[1, 0, 0, 0],
[1, 0, 0, 0]
] );
task2_pljava
--------------
{0,2,3,1}
(1 row)
*/
public class Task2 {
@Function( onNullInput = RETURNS_NULL, effects = IMMUTABLE )
public static final Integer[] task2_pljava( int size, int[] matrix ) throws Exception {
int row_index = 0;
Map<Integer, List<Integer>> ones = new HashMap<Integer, List<Integer>>();
int number_of_ones = 0;
for ( int i = 0; i < matrix.length; i++ ) {
number_of_ones += matrix[ i ];
if ( ( i + 1 ) % size == 0 || i == matrix.length ) {
if ( ! ones.containsKey( number_of_ones ) )
ones.put( number_of_ones, new LinkedList<Integer>() );
ones.get( number_of_ones ).add( row_index++ );
number_of_ones = 0;
}
}
List<Integer> keys = new LinkedList<Integer>( ones.keySet() );
Collections.sort( keys );
List<Integer> result = new LinkedList<Integer>();
for ( int k : keys ) {
List<Integer> values = ones.get( k );
Collections.sort( values );
result.addAll( values );
}
return result.toArray( new Integer[ result.size() ] );
}
}
|
