// Translate monotone MDDs to SAT
// Together with AMO translation
func convertMDD2Clauses(store mdd.IntervalMddStore, pb *Threshold) (clauses sat.ClauseSet) {
pred := sat.Pred("mdd" + strconv.Itoa(pb.Id))
top_lit := sat.Literal{true, sat.NewAtomP1(pred, store.Top)}
clauses.AddTaggedClause("Top", top_lit)
for _, n := range store.Nodes {
v_id, l, vds := store.ClauseIds(*n)
if !n.IsZero() && !n.IsOne() {
v_lit := sat.Literal{false, sat.NewAtomP1(pred, v_id)}
last_id := -1
for i, vd_id := range vds {
if last_id != vd_id {
vd_lit := sat.Literal{true, sat.NewAtomP1(pred, vd_id)}
if i > 0 {
literal := pb.Entries[len(pb.Entries)-l+i-1].Literal
clauses.AddTaggedClause("1B", v_lit, sat.Neg(literal), vd_lit)
} else {
clauses.AddTaggedClause("0B", v_lit, vd_lit)
}
}
last_id = vd_id
}
} else if n.IsZero() {
v_lit := sat.Literal{false, sat.NewAtomP1(pred, v_id)}
clauses.AddTaggedClause("False", v_lit)
} else if n.IsOne() {
v_lit := sat.Literal{true, sat.NewAtomP1(pred, v_id)}
clauses.AddTaggedClause("True", v_lit)
}
}
return
}
// Chains is a set of chains in order of the PB
// Chain: there are clauses xi <-xi+1 <- xi+2 ... <- xi+k, and xi .. xi+k are in order of PB
// assumption: chains are subsets of literals of PB and in their order
func CreateMDDChain(store *mdd.IntervalMddStore, K int64, entries []Entry, chains Chains) (int, int64, int64, error) {
l := len(entries) ///level
if store.MaxNodes < len(store.Nodes) {
return 0, 0, 0, errors.New("mdd max nodes reached")
}
//chain.Print()
//fmt.Println(l, K, entries)
if id, wmin_cache, wmax_cache := store.GetByWeight(l, K); id != -1 {
// fmt.Println("exists", l, K, "[", wmin, wmax, "]")
return id, wmin_cache, wmax_cache, nil
} else {
//domain of variable [0,1], extend to [0..n] soon (MDDs)
// entry of variable domain, atom: Dom: 2
var n mdd.IntervalNode
var err error
//glob.D(entries, chains)
glob.A(len(chains) == 0 || len(chains[0]) > 0, "if exists, then chain must contain at least 1 element")
if len(chains) > 0 && chains[0][0] == entries[0].Literal { //chain mode
chain := chains[0]
var jumpEntries []Entry
if len(entries) <= len(chain) { // can this happen if entries and chains are perfectly aligned?
jumpEntries = []Entry{}
} else {
jumpEntries = entries[len(chain):]
}
// iterate over the chain
n.Level = l
n.Children = make([]int, len(chain)+1)
n.Children[0], n.Wmin, n.Wmax, err = CreateMDDChain(store, K, jumpEntries, chains[1:])
if err != nil {
return 0, 0, 0, err
}
acc := int64(0)
// fmt.Printf("entries:%v chain: %v", entries, chain)
for i, _ := range chain {
glob.A(len(chain) <= len(entries), "chain and PB are not aligned!!!! ")
glob.A(chain[i] == entries[i].Literal, "chain and PB are not aligned!!!! ")
var wmin2, wmax2 int64
acc += entries[i].Weight
n.Children[i+1], wmin2, wmax2, err = CreateMDDChain(store, K-acc, jumpEntries, chains[1:])
n.Wmin = maxx(n.Wmin, wmin2+acc)
n.Wmax = min(n.Wmax, wmax2+acc)
if err != nil {
return 0, 0, 0, err
}
}
} else { //usual mode or for int-variables
dom := 2
n.Level = l
n.Children = make([]int, dom)
n.Wmin = math.MinInt64
n.Wmax = math.MaxInt64
var err error
for i := int64(0); i < int64(dom); i++ {
var wmin2, wmax2 int64
n.Children[i], wmin2, wmax2, err = CreateMDDChain(store, K-i*entries[0].Weight, entries[1:], chains)
n.Wmin = maxx(n.Wmin, wmin2+i*entries[0].Weight)
n.Wmax = min(n.Wmax, wmax2+i*entries[0].Weight)
if err != nil {
return 0, 0, 0, err
}
}
}
return store.Insert(n), n.Wmin, n.Wmax, nil
}
}