Merge pull request #9653 from fluca1978/PWC258

PWC 258

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
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+++ 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();
+;
+    }
+}