test.it.unimi.dsi.webgraph.ImmutableSubgraphTest Maven / Gradle / Ivy

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package it.unimi.dsi.webgraph;

/*		 
 * Copyright (C) 2003-2011 Sebastiano Vigna 
 *
 *  This program is free software; you can redistribute it and/or modify it
 *  under the terms of the GNU General Public License as published by the Free
 *  Software Foundation; either version 3 of the License, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 *  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, see .
 *
 */

import static org.junit.Assert.assertEquals;
import it.unimi.dsi.fastutil.ints.IntArrayList;

import java.util.Arrays;
import java.util.Collections;
import java.util.Random;

import org.junit.Test;

public class ImmutableSubgraphTest extends WebGraphTestCase {
	
	@Test
	public void testSubgraphs() {
		ImmutableGraph g, sg;
		final long seed = System.currentTimeMillis();
		System.err.println( "Seed: " + seed );
		final Random random = new Random( seed );
		
		for( int n = 1; n < 10; n++ ) { // Graph construction parameter
			g = ArrayListMutableGraph.newCompleteGraph( n, false ).immutableView();
			int[] randPerm = new int[ n ];
			for( int i = n; i-- != 0; ) randPerm[ i ] = i;
			Collections.shuffle( IntArrayList.wrap( randPerm ), random );
			
			for( int s = 1; s <= n; s++ ) {
				Arrays.sort( randPerm, 0, s );
				int nodes[] = new int[ s ];
				System.arraycopy( randPerm, 0, nodes, 0, s );
				sg = new ImmutableSubgraph( g, nodes );
				assertGraph( sg );
				final ArrayListMutableGraph completeGraph = ArrayListMutableGraph.newCompleteGraph( s, false );
				assertEquals( completeGraph.immutableView(), sg );
				assertEquals( sg, ImmutableSubgraph.asImmutableSubgraph( completeGraph.immutableView() ) );
				assertEquals( sg.hashCode(), completeGraph.hashCode() );
			}

			g = ArrayListMutableGraph.newCompleteBinaryIntree( n ).immutableView();
			for( int s = 1; s <= n; s++ ) {
				int[] nodes = new int[ ( 1 << s ) - 1 ];
				for( int j = ( 1 << s ) - 1; j-- != 0; ) nodes[ j ] = j;
				sg = new ImmutableSubgraph( g, nodes );
				assertGraph( sg );
				final ArrayListMutableGraph completeBinaryIntree = ArrayListMutableGraph.newCompleteBinaryIntree( s - 1 );
				final ImmutableGraph immutableView = completeBinaryIntree.immutableView();
				assertEquals( immutableView, sg );
				assertEquals( sg, ImmutableSubgraph.asImmutableSubgraph( immutableView ) );
				assertEquals( sg.hashCode(), completeBinaryIntree.hashCode() );
			}

			g = ArrayListMutableGraph.newCompleteBinaryOuttree( n ).immutableView();
			for( int s = 1; s <= n; s++ ) {
				int[] nodes = new int[ ( 1 << s ) - 1 ];
				for( int j = ( 1 << s ) - 1; j-- != 0; ) nodes[ j ] = j;
				sg = new ImmutableSubgraph( g, nodes );
				assertGraph( sg );

				final ArrayListMutableGraph completeBinaryOuttree = ArrayListMutableGraph.newCompleteBinaryOuttree( s - 1 );
				final ImmutableGraph immutableView = completeBinaryOuttree.immutableView();
				assertEquals( immutableView, sg );
				assertEquals( sg, ImmutableSubgraph.asImmutableSubgraph( immutableView ) );
				assertEquals( sg.hashCode(), completeBinaryOuttree.hashCode() );
			}

		}
	}

	
}