private static void caseSize2(CClausule clausule, CLiteralSet newLiteral, CClausuleSet newClausules)
{
// U'j
CLiteral y1 = CLiteral.generateLiteral(); // y1j
newLiteral.addLiteral(y1);
// C'j
bool[] direct = new bool[3];
CLiteral[] clausuleLiteral = new CLiteral[3];
clausuleLiteral[0] = clausule.getClausuleLiterals()[0]; // z1
direct[0] = clausule.getAreDirect()[0];
clausuleLiteral[1] = clausule.getClausuleLiterals()[1]; // z2
direct[1] = clausule.getAreDirect()[1];
clausuleLiteral[2] = y1; // y1j
direct[2] = true;
newClausules.addClausule(new CClausule(clausuleLiteral, direct)); // {z1, z2, y1j}
direct[2] = false; // ¬y1j
newClausules.addClausule(new CClausule(clausuleLiteral, direct)); // {z1, z2, ¬y1j}
}
public static CSATProblem reduct(CSATProblem problem)
{
CLiteralSet newLiterals = new CLiteralSet();
CClausuleSet newClausules = new CClausuleSet();
newLiterals.addAllLiterals(problem.getLiterals());
for (int i = 0; i < problem.getClausules().getClausules().Count; i++) { // por cada clausula de entrada
if (problem.getClausules().getClausules()[i].getSize() == 1)
caseSize1(problem.getClausules().getClausules()[i], newLiterals, newClausules);
else if (problem.getClausules().getClausules()[i].getSize() == 2)
caseSize2(problem.getClausules().getClausules()[i], newLiterals, newClausules);
else if (problem.getClausules().getClausules()[i].getSize() == 3)
caseSize3(problem.getClausules().getClausules()[i], newLiterals, newClausules);
else if (problem.getClausules().getClausules()[i].getSize() > 3)
caseSize4(problem.getClausules().getClausules()[i], newLiterals, newClausules);
}
return new CThreeSATProblem(newLiterals, newClausules);
}
private void example1()
{
bool[] directs = new bool[1];
CLiteral[] ls = new CLiteral[1];
ls[0] = CLiteral.generateLiteral(true);
directs[0] = true;
CLiteralSet literalSet = new CLiteralSet();
for (int i = 0; i < ls.Count(); i++)
literalSet.addLiteral(ls[i]);
CClausuleSet clausuleSet = new CClausuleSet();
clausuleSet.addClausule(new CClausule(ls, directs));
CSATProblem problem = new CSATProblem(literalSet, clausuleSet);
txOutput.Text = problem.toString();
txOutput.Text += problem.isSatisfactible().ToString() + Environment.NewLine;
txOutput.Text += CProblemReduction.reduct(problem).toString();
}
public CThreeSATProblem(CLiteralSet literals, CClausuleSet clausules)
: base(literals, clausules)
{
}
private void setClausules(CClausuleSet clausules)
{
this.clausules = clausules;
}
public CSATProblem(CLiteralSet literals, CClausuleSet clausules)
{
setLiterals(literals);
setClausules(clausules);
}
private static void caseSize4(CClausule clausule, CLiteralSet newLiteral, CClausuleSet newClausules)
{
bool[] direct = new bool[3];
CLiteral[] clausuleLiteral = new CLiteral[3];
clausuleLiteral[0] = clausule.getClausuleLiterals()[0]; // z1
direct[0] = clausule.getAreDirect()[0];
clausuleLiteral[1] = clausule.getClausuleLiterals()[1]; // z2
direct[1] = clausule.getAreDirect()[1];
CLiteral l = CLiteral.generateLiteral(); // y1j
newLiteral.addLiteral(l);
clausuleLiteral[2] = l;
direct[2] = true;
newClausules.addClausule(new CClausule(clausuleLiteral, direct)); // {z1, z2, y1j}
for (int i = 0; i < clausule.getSize() - 4; i++) { // 1 <= i <= k-4
clausuleLiteral[0] = l; // ¬yij
direct[0] = false;
clausuleLiteral[1] = clausule.getClausuleLiterals()[i + 2]; // zi+2
direct[1] = clausule.getAreDirect()[i + 2];
l = CLiteral.generateLiteral(); // yi+1j
clausuleLiteral[2] = l;
newLiteral.addLiteral(l);
direct[2] = true;
newClausules.addClausule(new CClausule(clausuleLiteral, direct)); // {{¬yij, zi+2, yi+1j} ; 1 <= i <= k-4}
}
clausuleLiteral[0] = l; // ¬yk - 3j
direct[0] = false;
clausuleLiteral[1] = clausule.getClausuleLiterals()[clausule.getSize() - 2]; // zk - 1
direct[1] = clausule.getAreDirect()[clausule.getSize() - 2];
clausuleLiteral[2] = clausule.getClausuleLiterals()[clausule.getSize() - 1]; // zk
direct[2] = clausule.getAreDirect()[clausule.getSize() - 1];
newClausules.addClausule(new CClausule(clausuleLiteral, direct)); // {¬yk-3j, zk-j, zk}
}
private static void caseSize3(CClausule clausule, CLiteralSet newLiteral, CClausuleSet newClausules)
{
newClausules.addClausule(clausule); //{cj}
}