diff options
Diffstat (limited to 'challenge-258/luca-ferrari/pljava/src/main/java/Task2.java')
| -rw-r--r-- | challenge-258/luca-ferrari/pljava/src/main/java/Task2.java | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/challenge-258/luca-ferrari/pljava/src/main/java/Task2.java b/challenge-258/luca-ferrari/pljava/src/main/java/Task2.java new file mode 100644 index 0000000000..a724c021c6 --- /dev/null +++ b/challenge-258/luca-ferrari/pljava/src/main/java/Task2.java @@ -0,0 +1,81 @@ +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(); +; + } +} |
