PuzzleTest.java

package com.igormaznitsa.prol.test;

import com.igormaznitsa.prol.io.DefaultProlStreamManagerImpl;
import com.igormaznitsa.prol.logic.Goal;
import com.igormaznitsa.prol.logic.ProlContext;
import com.igormaznitsa.prol.parser.ProlConsult;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.PrintWriter;
import junit.framework.TestCase;
import org.junit.Test;

public class PuzzleTest extends TestCase {

  @Test
  public void testPuzzle() throws Throwable {
    final ProlContext context = makeContext("sum(N1,N2,N):-sum1(N1,N2,N,0,0,[0,1,2,3,4,5,6,7,8,9],_)."
            + "sum1([],[],[],C,C,Digits,Digits)."
            + "sum1([D1|N1],[D2|N2],[D|N],C1,C,Digs1,Digs):-sum1(N1,N2,N,C1,C2,Digs1,Digs2),digitsum(D1,D2,C2,D,C,Digs2,Digs)."
            + "digitsum(D1,D2,C1,D,C,Digs1,Digs):-del_var(D1,Digs1,Digs2),del_var(D2,Digs2,Digs3),del_var(D,Digs3,Digs),S is D1+D2+C1,D is S mod 10,C is S//10."
            + "del_var(A,L,L):-nonvar(A),!."
            + "del_var(A,[A|L],L)."
            + "del_var(A,[B|L],[B|L1]):-del_var(A,L,L1)."
            + "puzzle1([D,O,N,A,L,D],[G,E,R,A,L,D],[R,O,B,E,R,T])."
            + "puzzle2([0,S,E,N,D],[0,M,O,R,E],[M,O,N,E,Y]).");
    final Goal goal = new Goal("puzzle1(X,Y,Z),sum(X,Y,Z).", context);

    final String[] puzzle1solXYZ = new String[]{"[5,2,6,4,8,5]", "[1,9,7,4,8,5]", "[7,2,3,9,7,0]"};

    final String[] puzzle2solZ = new String[]{"[0,8,3,5,6]", "[0,6,3,7,8]", "[0,4,2,8,9]", "[0,7,5,8,9]", "[0,9,3,4,6]", "[0,9,4,5,7]", "[0,4,1,7,9]", "[0,6,3,7,9]", "[0,8,4,6,9]", "[0,7,5,8,1]", "[0,9,2,3,7]", "[0,7,2,5,9]", "[0,8,3,5,9]", "[0,7,1,4,9]", "[0,8,1,3,9]", "[1,0,6,5,2]", "[0,3,1,8,5]", "[0,7,1,4,3]", "[0,8,2,4,3]", "[0,8,3,5,4]", "[0,8,4,6,5]", "[0,4,1,7,6]", "[0,3,1,8,7]", "[0,4,2,8,7]", "[0,6,4,8,7]"
    };

//        assertNotNull(goal.solve());
//        assertEquals(goal.getVarAsText("X"), puzzle1solXYZ[0]);
//        assertEquals(goal.getVarAsText("Y"), puzzle1solXYZ[1]);
//        assertEquals(goal.getVarAsText("Z"), puzzle1solXYZ[2]);
//        assertNull(goal.solve());
    final Goal goal2 = new Goal("puzzle2(X,Y,Z),sum(X,Y,Z).", context);

    for (int li = 0; li < puzzle2solZ.length; li++) {
      assertNotNull(goal2.solve());
      assertEquals(goal2.getVarAsText("Z"), puzzle2solZ[li]);
    }

    assertNull(goal2.solve());
  }

  private ProlContext makeContext(final String knowledgeBase) throws Exception {
    final ProlContext context = new ProlContext("PreparedGoal test", DefaultProlStreamManagerImpl.getInstance());
    final ProlConsult consult = new ProlConsult(knowledgeBase, context);
    consult.consult();

    // check that kb is right in its data export
    final ByteArrayOutputStream baos = new ByteArrayOutputStream(1024);
    final PrintWriter out = new PrintWriter(baos);
    context.getKnowledgeBase().write(out);
    out.flush();
    out.close();

    //System.out.println(new String(baos.toByteArray()));
    final ProlContext context1 = new ProlContext("PreparedGoal test", DefaultProlStreamManagerImpl.getInstance());
    final ProlConsult consult1 = new ProlConsult(new ByteArrayInputStream(baos.toByteArray()), context1);
    consult1.consult();

    return context1;
  }
}