void CTextNode::RebuildChildrenList()
{
// If possible init the children with XmlNodeRef's
m_children.clear();
if (m_xmlNode)
{
XmlNodeIt childrenIter(m_xmlNode);
for (XmlNodeRef child = childrenIter.first(); child; child = childrenIter.next())
{
m_children.push_back(CTextNode());
m_children.back() = child;
}
}
else
{
XmlConstNodeIt childrenIter(m_constXmlNode);
for (XmlConstNodeRef child = childrenIter.first(); child; child = childrenIter.next())
{
m_children.push_back(CTextNode());
m_children.back() = child;
}
}
}
int
BestFirst_Astar_Check(const NodeType &start,
int &uniquenodes, int &expandednodes)
{
uniquenodes = expandednodes = 0;
// copy start state
NodePtr<NodeType> pstart(start);
// calculate the heuristic value for this node
pstart->heuristic(*pstart);
// create open priority queue
List<NodePtr<NodeType> > openpq;
openpq.insertByValue(pstart);
uniquenodes++;
// create closed set
List<NodePtr<NodeType> > closedset;
// start search loop
for (NodePtr<NodeType> pnode; ! openpq.isEmpty(); )
{
// remove next node from priority open queue
openpq.removeAtFront(pnode);
// check if we have a goal node or not
if (pnode->isGoal())
{
// goal node, print solution
PrintSolution((NodeType *)pnode);
return(OK);
}
// generate the children of the current node
if (pnode->expand() != OK)
{
// unable to expand current node
return(NOTOK);
}
if (((++expandednodes%1000) == 0) && (expandednodes > 0))
{
cout << expandednodes << " nodes expanded." << endl;
cout << "current node is ... " << *pnode << endl;
}
// the following two lists are REQUIRED since the
// list iterator used below does NOT allow nodes
// to be deleted or inserted into the list while
// the iterator is traversing the list. the solution
// is to save the nodes that must be deleted and
// inserted in two separate lists, and after the
// iterator is done, then remove and add nodes to
// pnodes children list.
//
// list of nodes to delete from pnode children
List<NodePtr<NodeType> > nodesToRemove;
nodesToRemove.clear();
// list of nodes to add to pnode children
List<NodePtr<NodeType> > nodesToInsert;
nodesToInsert.clear();
// scan children and determine if they already exist.
ListIterator<NodePtr<NodeType> >
childrenIter(*pnode->getChildren());
for ( ; !childrenIter.done(); childrenIter++)
{
// set up link to parent
childrenIter()->setParent((NodeType *)pnode);
// calculate the heuristic value
childrenIter()->heuristic(*pstart);
// check if node already exists
NodePtr<NodeType> pchild(childrenIter());
NodePtr<NodeType> popen(childrenIter());
NodePtr<NodeType> pclosed(childrenIter());
// check if node was already generated
int inopen = NOMATCH;
int inclosed = NOMATCH;
if (( ! openpq.isEmpty()) &&
(inopen = openpq.retrieveByValue(popen)) == OK)
{
// check which path is better, the new
// path thru pnode, or the old one
// thru popen.
//
int childGvalue = pchild->getGvalue();
int oldGvalue = popen->getGvalue();
if (childGvalue < oldGvalue)
{
// reset old node parent pointer
popen->setParent(pchild->getParent());
popen->heuristic(*pstart);
}
// delete copy of node, and insert
// old node, popen, into children
// list of pnode.
//
nodesToRemove.insertAtFront(pchild);
nodesToInsert.insertAtFront(popen);
}
else if (( ! closedset.isEmpty()) &&
(inclosed = closedset.retrieveByValue(pclosed)) == OK)
{
// check which path is better, the new
// path thru pnode, or the old one
// thru pclosed.
//
int childGvalue = pchild->getGvalue();
int oldGvalue = pclosed->getGvalue();
if (childGvalue < oldGvalue)
{
// reset parent pointer
pclosed->setParent(pchild->getParent());
pclosed->heuristic(*pstart);
// check parent pointers for
// children of pclosed.
//
ListIterator<NodePtr<NodeType> > closedChildrenIter(*pclosed->getChildren());
for ( ; ! closedChildrenIter.done(); closedChildrenIter++)
{
// first we need to check if this child has
// the closed node as a parent. if it does,
// then do nothing. if it does not, then we
// have to compare g-values. if the existing
// g-value is smaller, then leave child node
// alone. if the the existing g-value is greater,
// then we have to reset the closed child parent
// pointer to point to the closed node since this
// path is now better.
//
NodePtr<NodeType> pclosedChild(closedChildrenIter());
NodePtr<NodeType> pclosedChildParent =
pclosedChild->getParent();
if ((NodeType *)pclosedChildParent == (NodeType *)pclosed)
{
// parent of closed child is the closed
// node, so just skip it.
continue;
}
TRACE();
// compare g-values to determine if the new path
// is better (cheaper) than the old path to
// the closed child node.
//
int oldClosedChildGvalue = pclosedChild->getGvalue();
pclosedChild->setParent(pclosed);
pclosedChild->heuristic(*pstart);
int newClosedChildGvalue = pclosedChild->getGvalue();
if (newClosedChildGvalue > oldClosedChildGvalue)
{
// set parent to old value
pclosedChild->setParent(pclosedChildParent);
pclosedChild->heuristic(*pstart);
}
}
}
// delete copy of node, and insert
// old node, pclosed, into children
// list of pnode.
//
nodesToRemove.insertAtFront(pchild);
nodesToInsert.insertAtFront(pclosed);
}
else if (inopen == NOMATCH && inclosed == NOMATCH)
{
// new node, place in open queue
openpq.insertByValue(pchild);
if (((++uniquenodes%1000) == 0) && (uniquenodes > 0))
{
cout << uniquenodes << " unique nodes." << endl;
}
}
else
{
// an error of some type
return(NOTOK);
}
}
// get pointer to nodes children list
List<NodePtr<NodeType> >
*pchildren = pnode->getChildren();
// remove children nodes
ListIterator<NodePtr<NodeType> >
nodesToRemoveIter(nodesToRemove);
for ( ; !nodesToRemoveIter.done(); nodesToRemoveIter++)
{
pchildren->removeByValue(nodesToRemoveIter());
}
// add children nodes
ListIterator<NodePtr<NodeType> >
nodesToInsertIter(nodesToInsert);
for ( ; !nodesToInsertIter.done(); nodesToInsertIter++)
{
pchildren->insertAtFront(nodesToInsertIter());
}
// store node in closed set
closedset.insertAtFront(pnode);
}
// finished with error
return(NOTOK);
}
int
BestFirst_Astar_WOCheck(const NodeType &start, const List<NodeType> &goals,
int &uniquenodes, int &expandednodes)
{
uniquenodes = expandednodes = 0;
// copy start state
NodePtr<NodeType> pstart(start);
// calculate the heuristic value for this node
pstart->heuristic(*pstart, goals);
// create open priority queue
List<NodePtr<NodeType> > openpq;
openpq.insertByValue(pstart);
uniquenodes++;
// create closed set
List<NodePtr<NodeType> > closedset;
// start search loop
for (NodePtr<NodeType> pnode; ! openpq.isEmpty(); )
{
// remove next node from priority open queue
openpq.removeAtFront(pnode);
// check if we have a goal node or not
if (goals.isInList(*pnode))
{
// goal node, print solution
PrintSolution((NodeType *)pnode);
return(OK);
}
// generate the children of the current node
if (pnode->expand() != OK)
{
// unable to expand current node
return(NOTOK);
}
if (((++expandednodes%1000) == 0) && (expandednodes > 0))
{
cout << expandednodes << " nodes expanded." << endl;
cout << "current node is ... " << *pnode << endl;
}
// set up links to parent and calculate the heuristic value
ListIterator<NodePtr<NodeType> >
childrenIter(*pnode->getChildren());
for ( ; !childrenIter.done(); childrenIter++)
{
// set up link to parent
childrenIter()->setParent((NodeType *)pnode);
// calculate the heuristic value
childrenIter()->heuristic(*pstart, goals);
// insert into open queue
openpq.insertByValue(childrenIter());
if (((++uniquenodes%1000) == 0) && (uniquenodes > 0))
{
cout << uniquenodes << " unique nodes." << endl;
}
}
// store node in closed set
closedset.insertAtFront(pnode);
}
// finished with error
return(NOTOK);
}
int
dfs(Proxy<NodeType> &pnode, int &threshold, int &next_threshold,
BinaryTree_AVL<DataType> &startlist,
BinaryTree_AVL<DataType> &otherlist)
{
int status;
// expand the current node's children
if ((status = pnode->expand(startlist, otherlist)) != OK)
{
// some type of error
ERRORD("expand() failed.", status, errno);
return(status);
}
// scan children for goal nodes
ListIterator<Proxy<NodeType> > childrenIter(*pnode->getChildren());
for ( ; !childrenIter.done(); childrenIter++)
{
// get pointer to child
Proxy<NodeType> pchild(childrenIter());
// set up link to parent
if (reporttype == ReportParent ||
reporttype == ReportBoth)
pchild->setParent(pnode);
// calculate the heuristic value
if ((status = pchild->heuristic(startlist, otherlist)) != OK)
{
ERRORD("heuristic() failed.", status, errno);
return(status);
}
// check if we have a goal node
status = pchild->isGoal(startlist, otherlist);
switch (status)
{
case OK:
break;
case NOMATCH:
case MAXDEPTHEXCEEDED:
continue;
case MAXCLAUSEEXCEEDED:
return(status);
case VALID:
// goal node, print solution
PrintSolution(pnode);
PrintRenameVariables(pnode);
return(VALID);
default:
// some type of error
ERRORD("isGoal() failed.", status, errno);
return(status);
}
// check if we continue, is threshold exceeded?
int childcost = pchild->getFvalue();
if (childcost <= threshold)
{
// continue depth-first search
status = dfs(pchild, threshold, next_threshold,
startlist, otherlist);
switch (status)
{
case OK:
case NOMATCH:
case MAXDEPTHEXCEEDED:
case NOTPROVEN:
break;
case MAXCLAUSEEXCEEDED:
return(MAXCLAUSEEXCEEDED);
case VALID:
// goal node, print solution
return(VALID);
default:
// some type of error
ERRORD("dfs() failed.", status, errno);
return(status);
}
}
else if (childcost < next_threshold)
{
next_threshold = childcost;
}
}
// goal was not not proven
return(NOTPROVEN);
}
int
BreadthFirstSearch(List<NodeType> &startstatelist,
BinaryTree_AVL<DataType> &startlist,
BinaryTree_AVL<DataType> &otherlist)
{
int status;
// track all states created
BinaryTree_AVL<String> allstates;
// create open priority queue
List<Proxy<NodeType> > openpq;
// copy list of start states
int nodedepth = 1;
ListIterator<NodeType> startstateIter(startstatelist);
for ( ; !startstateIter.done(); startstateIter++)
{
// copy start state
Proxy<NodeType> pstart(startstateIter());
// set start node depth
pstart->setDepth(nodedepth);
// insert start state into open queue
if ((status = openpq.insertAtEnd(pstart)) != OK)
{
ERRORD("insertAtFront() failed.", status, errno);
return(status);
}
}
// start search loop
for (Proxy<NodeType> pnode; ! openpq.isEmpty(); )
{
// remove next node from priority open queue
if ((status = openpq.removeAtFront(pnode)) != OK)
{
ERRORD("removeAtFront() failed.", status, errno);
return(status);
}
// set current node depth
nodedepth = pnode->getDepth();
// check if we have a goal node or not
status = pnode->isGoal(startlist, otherlist);
switch (status)
{
case OK:
break;
case NOMATCH:
case MAXDEPTHEXCEEDED:
// no clauses were generated. skip further
// processing of this node.
continue;
case VALID:
// goal node, print solution
PrintSolution(pnode);
PrintRenameVariables(pnode);
// check if more than one solutions is required
solutionsfound += 1;
statistics[SolutionsFound] += 1;
totalstatistics[TotalSolutionsFound] += 1;
if (solutionsfound >= solutionsrequired)
return(VALID);
continue;
case MAXCLAUSEEXCEEDED:
// check if any solutions were found
if (solutionsfound > 0)
return(VALID);
else
return(NOTPROVEN);
default:
// some type of error
ERRORD("isGoal() failed.", status, errno);
return(status);
}
// generate the children of the current node
if ((status = pnode->expand(startlist, otherlist)) != OK)
{
ERRORD("expand() failed.", status, errno);
return(status);
}
// set up links to parent and calculate the heuristic value
ListIterator<Proxy<NodeType> >
childrenIter(*pnode->getChildren());
for ( ; !childrenIter.done(); childrenIter++)
{
// pointer to child
Proxy<NodeType> pchild(childrenIter());
// set up link to parent
if (reporttype == ReportParent ||
reporttype == ReportBoth)
pchild->setParent(pnode);
// insert into queue
if (!bfswithchecks)
{
pchild->setDepth(nodedepth+1);
if ((status = openpq.insertAtEnd(
pchild)) != OK)
{
ERRORD("insertAtEnd() failed.",
status, errno);
return(status);
}
}
else
{
statistics[RedundantClauseTestsAttempted] += 1;
totalstatistics[TotalRedundantClauseTestsAttempted] += 1;
String newnode(pchild->getNormalizedClauses());
if (allstates.retrieve(newnode) == NOMATCH)
{
pchild->setDepth(nodedepth+1);
if ((status = openpq.insertAtEnd(
pchild)) != OK)
{
ERRORD("insertAtEnd() failed.",
status, errno);
return(status);
}
}
else
{
statistics[RedundantClausesRejected] += 1;
totalstatistics[TotalRedundantClausesRejected] += 1;
}
}
}
if (bfswithchecks)
{
if (allstates.insert(pnode->getNormalizedClauses()) != OK)
{
ERRORD("insert() failed.", status, errno);
return(status);
}
}
}
// check if any solutions were found
if (solutionsfound > 0)
return(VALID);
else
return(NOTPROVEN);
}
int
DepthFirstHillClimbSearch(List<NodeType> &startstatelist,
BinaryTree_AVL<DataType> &startlist,
BinaryTree_AVL<DataType> &otherlist)
{
int status;
// track all states created
BinaryTree_AVL<String> allstates;
// create open stack for traversal
List<Proxy<NodeType> > openstack;
// keep track of current path here instead of
// using parent pointers. parent pointers cause
// cycles and reference-counted pointers cannot
// deal with cyclic data structures. they cause
// major memory leaks.
//
int nodedepth = 1;
List<Proxy<NodeType> > currentpath;
// copy list of start states
ListIterator<NodeType> startstateIter(startstatelist);
for ( ; !startstateIter.done(); startstateIter++)
{
// copy start state
Proxy<NodeType> pstart(startstateIter());
// calculate the heuristic value for this node
if ((status = pstart->heuristic(startlist, otherlist)) != OK)
{
ERRORD("heuristic() failed.", status, errno);
return(status);
}
// set start node depth
pstart->setDepth(nodedepth);
// insert start state into open queue
if ((status = openstack.insertOrdered(pstart)) != OK)
{
ERRORD("insertOrdered() failed.", status, errno);
return(status);
}
}
// children priority queue
List<Proxy<NodeType> > childpq;
// start search loop
int olddepth = nodedepth;
Proxy<NodeType> pchild;
for (Proxy<NodeType> pnode; ! openstack.isEmpty(); )
{
// remove next node from priority open queue
if ((status = openstack.removeAtFront(pnode)) != OK)
{
ERRORD("removeAtFront() failed.", status, errno);
return(status);
}
// check if we have a goal node or not
status = pnode->isGoal(startlist, otherlist);
switch (status)
{
case OK:
// update current path
if ((status = updatepath(nodedepth,
olddepth, pnode, currentpath)) != OK)
return(status);
break;
case NOMATCH:
case MAXDEPTHEXCEEDED:
// no clauses were generated. skip further
// processing of this node.
continue;
case VALID:
// update current path
if ((status = updatepath(nodedepth,
olddepth, pnode, currentpath)) != OK)
return(status);
// goal node, print solution
PrintSolution(pnode);
PrintSolution(currentpath);
PrintRenameVariables(pnode);
// check if more than one solutions is required
solutionsfound += 1;
statistics[SolutionsFound] += 1;
totalstatistics[TotalSolutionsFound] += 1;
if (solutionsfound >= solutionsrequired)
return(VALID);
continue;
case MAXCLAUSEEXCEEDED:
// check if any solutions were found
if (solutionsfound > 0)
return(VALID);
else
return(NOTPROVEN);
default:
// some type of error
ERRORD("isGoal() failed.", status, errno);
return(status);
}
// generate the children of the current node
if ((status = pnode->expand(startlist, otherlist)) != OK)
{
ERRORD("expand() failed.", status, errno);
return(status);
}
// clear children priority queue
childpq.clear();
// set up links to parent and calculate the heuristic value
ListIterator<Proxy<NodeType> >
childrenIter(*pnode->getChildren());
for ( ; !childrenIter.done(); childrenIter++)
{
// pointer to child
pchild = childrenIter();
// set up link to parent
if (reporttype == ReportParent ||
reporttype == ReportBoth)
pchild->setParent(pnode);
// calculate the heuristic value
if ((status = pchild->heuristic(
startlist, otherlist)) != OK)
{
ERRORD("heuristic() failed.", status, errno);
return(status);
}
// insert child into a priority queue to order
pchild->setDepth(nodedepth+1);
if ((status = childpq.insertOrdered(pchild)) != OK)
{
ERRORD("insertOrdered() failed.",
status, errno);
return(status);
}
}
// insert nodes into stack ordered by heuristic value
while (!childpq.isEmpty())
{
// remove next node from priority open queue
if ((status = childpq.removeAtEnd(pchild)) != OK)
{
ERRORD("removeAtEnd() failed.",
status, errno);
return(status);
}
// insert node into a stack
if (!bfswithchecks)
{
if ((status = openstack.insertAtFront(
pchild)) != OK)
{
ERRORD("insertAtFront() failed.",
status, errno);
return(status);
}
}
else
{
statistics[RedundantClauseTestsAttempted] += 1;
totalstatistics[TotalRedundantClauseTestsAttempted] += 1;
String newnode(pchild->getNormalizedClauses());
if (allstates.retrieve(newnode) == NOMATCH)
{
if ((status = openstack.insertAtFront(
pchild)) != OK)
{
ERRORD("insertAtFront() failed.",
status, errno);
return(status);
}
}
else
{
statistics[RedundantClausesRejected] += 1;
totalstatistics[TotalRedundantClausesRejected] += 1;
}
}
}
// children are now in the queue. release pointers to
// children stored in node.
//
pnode->getChildren()->clear();
if (bfswithchecks)
{
if (allstates.insert(pnode->getNormalizedClauses()) != OK)
{
ERRORD("insert() failed.", status, errno);
return(status);
}
}
}
// check if any solutions were found
if (solutionsfound > 0)
return(VALID);
else
return(NOTPROVEN);
}
