blob: a724c021c690044785632c690ef9a4f7886a7c4c (
plain)
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
76
77
78
79
80
81
|
package PWC258;
/**
* PL/Java implementation for PWC 258
* Task 2
* See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-258>
*
*
* To compile on the local machine:
$ export JAVA_HOME=/usr/lib/jvm/java-17-openjdk-amd64/ # if not already set
$ mvn clean build
$ scp target/PWC258.jar luca@rachel:/tmp
* To install into PostgreSQL execute:
select sqlj.install_jar( 'file:///tmp/PWC258-1.jar', 'PWC258', true );
select pwc258.task2_pljava();
and then to redeploy:
select sqlj.replace_jar( 'file:///tmp/PWC258-1.jar', 'PWC258', true );
*/
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.*;
import java.util.stream.*;
import java.sql.SQLException;
import java.util.logging.*;
import java.sql.ResultSet;
import java.sql.Date;
public class Task2 {
private final static Logger logger = Logger.getAnonymousLogger();
@Function( schema = "pwc258",
onNullInput = RETURNS_NULL,
effects = IMMUTABLE )
public static final int task2_pljava( int k, int[] nums ) throws SQLException {
logger.log( Level.INFO, "Entering task2_pljava" );
// int sum = 0;
// int count = 0;
// for ( int i = 0; i < nums.length; i++ ) {
// count = 0;
// for ( String d : Integer.toBinaryString( i ).split( "" ) )
// if ( d.equals( "1" ) )
// count++;
// if ( count == k )
// sum += nums[ i ];
// }
// return sum
return IntStream.range( 0, nums.length )
.map( current -> {
int ones = 0;
for ( String d : Integer.toBinaryString( current ).split( "" ) )
if ( d.equals( "1" ) )
ones ++;
if ( ones == k )
return nums[ current ];
else
return 0;
} ).sum();
;
}
}
|
