public override _Term Replace(_MGU s)
{
_Term result = new _Variable(this);
for (int i = 0; i < s.Count; ++i)
{
if (s[i].Arg1.CompareTo(result))
{
if (s[i].Arg2.GetType() != _TypeOfTerm.COMPOSITE)
{
result = _Term.arrPatternObject[(int)s[i].Arg2.GetType()].NewObject(s[i].Arg2);
if (result.GetType() == _TypeOfTerm.VARIABLE)
{
result = result.Replace(s);
}
}
else
{
result = s[i].Arg2.Replace(s);
}
break;
}
}
return(result);
}
public _BackwardChaining(_KB p)
{
mKB = new _KB();
#region for (int i = 0; i < p.Count; ++i)
for (int i = 0; i < p.Count; ++i)
{
_Horn horn = (_Horn)p[i];
ArrayList left = new ArrayList();
_Term right;
_MGU tempMgu = new _MGU();
#region Lay tat ca cac bien o 1 dong
ArrayList arrVal = new ArrayList();
arrVal = horn.Right.GetListOfVariable2();
for (int j = 0; j < horn.Left.Count; ++j)
{
_Term tempTerm = (_Term)horn.Left[j];
ArrayList arrValLeft = tempTerm.GetListOfVariable2();
for (int l = 0; l < arrValLeft.Count; ++l)
{
_Variable v1 = (_Variable)arrValLeft[l];
Boolean flag1 = false;
for (int k = 0; k < arrVal.Count; ++k)
{
_Variable v2 = (_Variable)arrVal[k];
if (v1.CompareTo(v2))
{
flag1 = true;
break;
}
}
if (flag1 == false)
{
arrVal.Add(arrValLeft[l]);
}
}
}
#endregion
for (int j = 0; j < arrVal.Count; ++j)
{
_Variable t = (_Variable)arrVal[j];
_Term tempArg2 = new _Variable(t.Name + "." + i);
tempMgu.Add(new _Element(t, tempArg2));
}
for (int j = 0; j < horn.Left.Count; ++j)
{
_Term temp = (_Term)horn.Left[j];
left.Add(temp.Replace(tempMgu));
}
right = horn.Right.Replace(tempMgu);
mKB.Add(new _Horn(left, right));
}
#endregion
}
public _Element Find(_Variable x)
{
_Element result = null;
_Element temp;
for (int i = 0; i < mContent.Count; ++i)
{
temp = (_Element)mContent[i];
if (temp.IsBelong(x) == true)
{
result = new _Element(temp);
break;
}
}
return(result);
}
private Boolean Unify_var(_Variable var, _Term x, ref _MGU s)
{
_Element val;
if ((val = s.Find(var)) != null)
{
return(Run(val.Arg2, x, ref s));
}
else
if ((val = s.Find(x)) != null)
{
return(Run(var, val.Arg1, ref s));
}
else
if (x.IsAppear(var) == true)
{
return(false);
}
else
{
s.Add(new _Element(var, x));
return(true);
}
}
public Boolean IsBelong(_Variable x)
{
return(mArg1.CompareTo(x));
}
public _Element(_Variable var, _Term x)
{
Init(var, x);
}
private void Init(_Variable var, _Term x)
{
mArg1 = new _Variable(var);
mArg2 = _Term.arrPatternObject[(int)x.GetType()].NewObject(x);
}
private void Run(ArrayList goals, _MGU theta)
{
#region if (goals.Count == 0)
if (goals.Count == 0)
{
mResult.Add(theta);
ArrayList ListVariable = mG.GetListOfVariable();
_MGU result = new _MGU();
#region for (int j = 0; j < ListVariable.Count; ++j) : thay tap the thanh ket qua cuoi cung
for (int j = 0; j < ListVariable.Count; ++j)
{
_Variable val = (_Variable)ListVariable[j];
result.Add(new _Element(new _Variable(val.Name.Replace("?", "")), val.Replace(theta)));
}
#endregion
#region Kiem tra ket qua vua tim duoc da co hay chu
Boolean flag = false;
for (int i = 0; i < mResult.Count; ++i)
{
_MGU temp = (_MGU)mResult[i];
if (temp.CompareTo(result) == true)
{
flag = true;
break;
}
}
#endregion
if (flag == false) // Chi nhan cac ket qua chua co
{
mResult.Add(result);
}
return;
}
#endregion
_Term firstGoals = (_Term)goals[0];
_Term q1 = firstGoals.Replace(theta);
#region for (int i = 0; i < mKB.Count; ++i)
for (int i = 0; i < mKB.Count; ++i)
{
_Term q = mKB[i].Right;
_Unify u = new _Unify(q, q1);
_MGU Temptheta1; // Chua phep the cua viec dong nhat q1 voi q, co dang {x/y, y/A)
_MGU tempMGU = new _MGU(); // Chua phep the o dang trung gian, chi dung de the vao p1,...,pn, dang {x/x0, y/y0}
_MGU theta1 = new _MGU(); // Phep the that su (da thay doi ten bien) cua phep dong nhat q1 voi q, co dang {x0/y0, y0/A}
#region if (u.Run(out Temptheta1) == true)
if (u.Run(out Temptheta1) == true)
{
#region for (int j = 0; j < Temptheta1.Count; ++j) doi ten bien trong tap the de co tap the moi la theta1
ArrayList arrIndex = new ArrayList(); // Ghi nhan nhung bien nao xuat hien (tuc la bien count tang)
for (int j = 0; j < Temptheta1.Count; ++j)
{
#region if (theta.Find((_Term)Temptheta1[j].Arg1) != null)
// Neu bien da co trong theta (tuc la bien co lien quan den cac phep the khac),
// thi khong doi ten
if (theta.Find((_Term)Temptheta1[j].Arg1) != null)
{
theta1.Add(Temptheta1[j]);
continue;
}
#endregion
#region for (k = 0; k < mVariable.Count; ++k)
// Kiem tra xem bien cua Temptheta1[j] da xuat hien chua
int k;
Boolean flag = false;
for (k = 0; k < mVariable.Count; ++k)
{
_Item tempItem = (_Item)mVariable[k];
if (Temptheta1[j].Arg1.CompareTo(tempItem.val))
{
flag = true;
break;
}
}
#endregion
#region if (flag == false)
// Neu chua co bien thi them vao tap hop, con neu bien da xuat hien thi tang so lan xuat hien len 1 don vi
_Item ItemTemp;
if (flag == false)
{
ItemTemp = new _Item();
ItemTemp.val = new _Variable(Temptheta1[j].Arg1);
ItemTemp.Count = 0;
mVariable.Add(ItemTemp);
}
else
{
ItemTemp = (_Item)mVariable[k];
ItemTemp.Count++;
mVariable[k] = ItemTemp;
arrIndex.Add(k);
// Doi ten bien va dua vao tap theta1
}
// theta1.Add(new _Element(new _Variable(ItemTemp.val.Name + "_" + ItemTemp.Count.ToString()), Temptheta1[j].Arg2));
_Term tempArg2 = new _Variable(ItemTemp.val.Name + "_" + ItemTemp.Count.ToString());
theta1.Add(new _Element(Temptheta1[j].Arg1, tempArg2));
theta1.Add(new _Element((_Variable)tempArg2, Temptheta1[j].Arg2));
tempMGU.Add(new _Element(Temptheta1[j].Arg1, theta1[theta1.Count - 1].Arg1));
#endregion
}
#endregion
_MGU tempTheta = theta + theta1;
#region tempGoals = [p1,...,pn] | Rest(goals)
ArrayList tempGoals = new ArrayList();
#region for (int j = 0; j < mKB[i].Left.Count; ++j)
// Them p1,...,pn vao tempGoals, cac phan tu truoc khi them vao da duoc doi ten bien
for (int j = 0; j < mKB[i].Left.Count; ++j)
{
_Term t = (_Term)mKB[i].Left[j];
// tempGoals.Add(t.Replace(tempMGU));
tempGoals.Add(t.Replace(theta1));
}
#endregion
#region for (int j = 1; j < goals.Count; ++j)
// Them cac rest(goals) vao tempGoals, loai bo cac phan tu trung
for (int j = 1; j < goals.Count; ++j)
{
Boolean flag = false;
_Term t2 = (_Term)goals[j];
for (int k = 0; k < tempGoals.Count; ++k)
{
_Term t1 = (_Term)tempGoals[k];
if (t1.CompareTo(t2))
{
flag = true;
break;
}
}
if (flag == false)
{
tempGoals.Add(goals[j]);
}
}
#endregion
#endregion
Run(tempGoals, tempTheta);
#region for (int j = 0; j < arrIndex.Count; ++j)
// Giam bien count, chi ap dung cho nhung bien ma count thay doi
for (int j = 0; j < arrIndex.Count; ++j)
{
_Item ItemTemp;
int k = (int)arrIndex[j];
ItemTemp = (_Item)mVariable[k];
ItemTemp.Count--;
mVariable[k] = ItemTemp;
}
#endregion
}
#endregion
}
#endregion
}