public List <Lit> CalcReason(Solver s, Lit p)
{
List <Lit> x = new List <Lit>();
for (int i = (p == Lit.LIT_UNDEF ? 0 : 1); i < this.lits.Count; i++)
{
//x.Add(this.lits[i]);
x.Add(Lit.NegativeLit(this.lits[i]));
}
return(x);
}
// Page 15
private void Analyze(Clause confl, out List <Lit> out_learnt, out int btlevel)
{
int counter = 0;
Lit p = Lit.LIT_UNDEF;
List <Lit> p_reason;
List <int> seen = new List <int>(); // May need to optimize this
btlevel = 0;
out_learnt = new List <Lit>();
out_learnt.Add(Lit.LIT_UNDEF); // Reserve space for lits[0]
do
{
p_reason = confl.CalcReason(this, p);
foreach (Lit q in p_reason)
{
if (!seen.Contains(q.Var))
{
seen.Add(q.Var);
if (this.level[q.Var] == this.DecisionLevel)
{
++counter;
}
else if (this.level[q.Var] > 0)
{
//out_learnt.Add(Lit.LitFromVal(q.Val));
out_learnt.Add(Lit.NegativeLit(q));
btlevel = Math.Max(btlevel, this.level[q.Var]);
}
}
}
do
{
p = Lit.LitFromVal(this.trail.Peek());
confl = this.reason[p.Var];
this.UndoOne();
} while (!seen.Contains(p.Var));
--counter;
} while(counter > 0);
out_learnt[0] = Lit.NegativeLit(p);
}
