Merge pull request #9822 from fluca1978/PWC262

PWC 262

1 files changed, 66 insertions, 0 deletions

diff --git a/challenge-262/luca-ferrari/pljava/src/main/java/Task2.java b/challenge-262/luca-ferrari/pljava/src/main/java/Task2.java
new file mode 100644
index 0000000000..0260bb29b3
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+++ b/challenge-262/luca-ferrari/pljava/src/main/java/Task2.java
@@ -0,0 +1,66 @@
+
+
+
+package PWC262;
+
+/**
+ * PL/Java implementation for PWC 262
+ * Task 2
+ * See <https://perlweeklychallenge.org/blog/perl-weekly-challenge-262>
+ *
+ *
+ * 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/PWC262-1.jar  luca@rachel:/tmp
+
+
+ * To install into PostgreSQL execute:
+
+ select sqlj.install_jar( 'file:///tmp/PWC262-1.jar', 'PWC262', true );
+ select sqlj.set_classpath( 'public', 'PWC262' );
+
+ select pwc262.task2_pljava();
+
+ and then to redeploy:
+
+ select sqlj.replace_jar( 'file:///tmp/PWC262-1.jar', 'PWC262', 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 = "pwc262",
+	       onNullInput = RETURNS_NULL,
+	       effects = IMMUTABLE )
+    public static final int task2_pljava( int k, int[] nums ) throws SQLException {
+	logger.log( Level.INFO, "Entering pwc262.task2_pljava" );
+
+	int pairs = 0;
+	for ( int i = 0; i < nums.length; i++ )
+	    for ( int j = i + 1; j < nums.length; j++ )
+		if ( nums[ i ] != nums[ j ]
+		     || ( i * j ) % k != 0 )
+		    continue;
+		else
+		    pairs++;
+
+	return pairs;
+
+    }
+}