private void ShuffleFringe()
{
int n = this.fringe.Count;
Random rnd = new Random();
while (n > 1)
{
int k = (rnd.Next(0, n) % n);
n--;
Clouse value = this.fringe[k];
this.fringe[k] = this.fringe[n];
this.fringe[n] = value;
}
}
/*
* this is some test fot the algorithm relaying on the example from class
* */
public List <Clouse> build_example()
{
List <Clouse> formula = new List <Clouse>();
Atomic a = new Atomic("ok", false);
Atomic a2 = new Atomic("uf", false);
List <Atomic> l1 = new List <Atomic>();
l1.Add(a);
l1.Add(a2);
Clouse c1 = new Clouse(l1, 0);
c1.unknown = 2;
c1.unknown_literals.Add(a);
c1.unknown_literals.Add(a2);
formula.Add(c1);
/////
Atomic a3 = new Atomic("ok", false);
Atomic a4 = new Atomic("a", true);
List <Atomic> l2 = new List <Atomic>();
l2.Add(a3);
l2.Add(a4);
Clouse c2 = new Clouse(l2, 0);
c2.unknown = 2;
c2.unknown_literals.Add(a3);
c2.unknown_literals.Add(a4);
formula.Add(c2);
/////
Atomic a5 = new Atomic("nco", true);
Atomic a6 = new Atomic("ia", false);
List <Atomic> l3 = new List <Atomic>();
l3.Add(a5);
l3.Add(a6);
Clouse c3 = new Clouse(l3, 0);
c3.unknown = 2;
c3.unknown_literals.Add(a5);
c3.unknown_literals.Add(a6);
formula.Add(c3);
/////
Atomic a7 = new Atomic("a", false);
Atomic a8 = new Atomic("ia", false);
List <Atomic> l4 = new List <Atomic>();
l4.Add(a7);
l4.Add(a8);
Clouse c4 = new Clouse(l4, 0);
c4.unknown = 2;
c4.unknown_literals.Add(a7);
c4.unknown_literals.Add(a8);
formula.Add(c4);
/////
Atomic a11 = new Atomic("ok", false);
Atomic a12 = new Atomic("rf", false);
List <Atomic> l6 = new List <Atomic>();
l6.Add(a11);
l6.Add(a12);
Clouse c6 = new Clouse(l6, 0);
c6.unknown = 2;
c6.unknown_literals.Add(a11);
c6.unknown_literals.Add(a12);
formula.Add(c6);
/////
Atomic a13 = new Atomic("ia", true);
Atomic a14 = new Atomic("rf", false);
List <Atomic> l7 = new List <Atomic>();
l7.Add(a13);
l7.Add(a14);
Clouse c7 = new Clouse(l7, 0);
c7.unknown = 2;
c7.unknown_literals.Add(a13);
c7.unknown_literals.Add(a14);
formula.Add(c7);
/////
Atomic a15 = new Atomic("nci", false);
Atomic a16 = new Atomic("a", false);
Atomic a17 = new Atomic("nco", true);
List <Atomic> l8 = new List <Atomic>();
l8.Add(a15);
l8.Add(a16);
l8.Add(a17);
Clouse c8 = new Clouse(l8, 0);
c8.unknown = 3;
c8.unknown_literals.Add(a15);
c8.unknown_literals.Add(a16);
c8.unknown_literals.Add(a17);
formula.Add(c8);
/////
Atomic a18 = new Atomic("uf", false);
Atomic a19 = new Atomic("rf", false);
List <Atomic> l9 = new List <Atomic>();
l9.Add(a18);
l9.Add(a19);
Clouse c9 = new Clouse(l9, 0);
c9.unknown = 2;
c9.unknown_literals.Add(a18);
c9.unknown_literals.Add(a19);
formula.Add(c7);
/////
Atomic a20 = new Atomic("rf", true);
List <Atomic> l10 = new List <Atomic>();
l10.Add(a20);
Clouse c10 = new Clouse(l10, 0);
c10.unknown = 1;
c10.unknown_literals.Add(a20);
formula.Add(c10);
/////
Atomic a21 = new Atomic("ok", true);
List <Atomic> l11 = new List <Atomic>();
l11.Add(a21);
Clouse c11 = new Clouse(l11, 0);
c11.unknown = 1;
c11.unknown_literals.Add(a21);
formula.Add(c11);
return(formula);
}