namespace lyx {
-bool Graph::bfs_init(int s, bool clear_visited)
+bool Graph::bfs_init(int s, bool clear_visited, queue<int> & Q)
{
if (s < 0)
return false;
-
- Q_ = queue<int>();
+
+ if (!Q.empty())
+ Q = queue<int>();
if (clear_visited) {
vector<Vertex>::iterator it = vertices_.begin();
it->visited = false;
}
if (!vertices_[s].visited) {
- Q_.push(s);
+ Q.push(s);
vertices_[s].visited = true;
}
return true;
}
-void Graph::clearMarks()
-{
- Arrows::iterator it = arrows_.begin();
- Arrows::iterator const en = arrows_.end();
- for (; it != en; ++it)
- it->marked = false;
-}
-
-
-vector<int> const
+Graph::EdgePath const
Graph::getReachableTo(int target, bool clear_visited)
{
- vector<int> result;
- if (!bfs_init(target, clear_visited))
+ EdgePath result;
+ queue<int> Q;
+ if (!bfs_init(target, clear_visited, Q))
return result;
// Here's the logic, which is shared by the other routines.
- // Q_ holds a list of nodes we have been able to reach (in this
+ // Q holds a list of nodes we have been able to reach (in this
// case, reach backwards). It is initialized to the current node
// by bfs_init, and then we recurse, adding the nodes we can reach
// from the current node as we go. That makes it a breadth-first
// search.
- while (!Q_.empty()) {
- int const current = Q_.front();
- Q_.pop();
+ while (!Q.empty()) {
+ int const current = Q.front();
+ Q.pop();
if (current != target || formats.get(target).name() != "lyx")
result.push_back(current);
const int cv = (*it)->from;
if (!vertices_[cv].visited) {
vertices_[cv].visited = true;
- Q_.push(cv);
+ Q.push(cv);
}
}
}
}
-vector<int> const
+Graph::EdgePath const
Graph::getReachable(int from, bool only_viewable,
- bool clear_visited)
+ bool clear_visited, set<int> excludes)
{
- vector<int> result;
- if (!bfs_init(from, clear_visited))
+ EdgePath result;
+ queue<int> Q;
+ if (!bfs_init(from, clear_visited, Q))
return result;
- while (!Q_.empty()) {
- int const current = Q_.front();
- Q_.pop();
+ while (!Q.empty()) {
+ int const current = Q.front();
+ Q.pop();
Format const & format = formats.get(current);
if (!only_viewable || !format.viewer().empty())
result.push_back(current);
int const cv = (*cit)->to;
if (!vertices_[cv].visited) {
vertices_[cv].visited = true;
- Q_.push(cv);
+ if (excludes.find(cv) == excludes.end())
+ Q.push(cv);
}
}
}
if (from == to)
return true;
- if (to < 0 || !bfs_init(from))
+ queue<int> Q;
+ if (to < 0 || !bfs_init(from, true, Q))
return false;
- while (!Q_.empty()) {
- int const current = Q_.front();
- Q_.pop();
+ while (!Q.empty()) {
+ int const current = Q.front();
+ Q.pop();
if (current == to)
return true;
int const cv = (*cit)->to;
if (!vertices_[cv].visited) {
vertices_[cv].visited = true;
- Q_.push(cv);
+ Q.push(cv);
}
}
}
Graph::EdgePath const Graph::getPath(int from, int to)
{
- EdgePath path;
if (from == to)
- return path;
-
- if (to < 0 || !bfs_init(from))
- return path;
-
- // In effect, the way this works is that we construct a sub-graph
- // by starting at "from" and following the arrows outward. Instead
- // of actually constructing a sub-graph, though, we "mark" the
- // arrows we traverse as we go. Once we hit "to", we abort the
- // marking process and then call getMarkedPath() to reconstruct
- // the marked path.
- bool found = false;
- clearMarks();
- while (!Q_.empty()) {
- int const current = Q_.front();
- Q_.pop();
+ return EdgePath();
+
+ queue<int> Q;
+ if (to < 0 || !bfs_init(from, true, Q))
+ return EdgePath();
+
+ vector<EdgePath> pathes;
+ pathes.resize(vertices_.size());
+ while (!Q.empty()) {
+ int const current = Q.front();
+ Q.pop();
vector<Arrow *>::const_iterator cit =
vertices_[current].out_arrows.begin();
int const cv = (*cit)->to;
if (!vertices_[cv].visited) {
vertices_[cv].visited = true;
- Q_.push(cv);
- (*cit)->marked = true;
+ Q.push(cv);
+ // NOTE If we wanted to collect all the paths, then
+ // we just need to collect them here and not worry
+ // about "visited".
+ EdgePath lastpath = pathes[(*cit)->from];
+ lastpath.push_back((*cit)->id);
+ pathes[cv] = lastpath;
}
if (cv == to) {
- found = true;
- break;
+ return pathes[cv];
}
}
}
- if (!found)
- return path;
-
- getMarkedPath(from, to, path);
- return path;
+ // failure
+ return EdgePath();
}
-// We assume we have marked the graph, as in getPath(). We also
-// assume that we have done so in such a way as to guarantee a
-// marked path from "from" to "to".
-// We then start at "to" and find the arrow leading to it that
-// has been marked. We add that to the path we are constructing,
-// step back on that arrow, and continue the process (i.e., recurse).
-void Graph::getMarkedPath(int from, int to, EdgePath & path) {
- if (from == to) {
- reverse(path.begin(), path.end());
- return;
- }
- // find marked in_arrow
- vector<Arrow *>::const_iterator it = vertices_[to].in_arrows.begin();
- vector<Arrow *>::const_iterator const en = vertices_[to].in_arrows.end();
- for (; it != en; ++it)
- if ((*it)->marked)
- break;
- if (it == en) {
- // debug code to try to figure out what's up.
- LYXERR0("Failed to find marked arrow.\n"
- "From: " << from << ", To: " << to);
- dumpGraph();
- LASSERT(false, /* */);
- return;
- }
- path.push_back((*it)->id);
- getMarkedPath(from, (*it)->from, path);
-}
-
-
void Graph::init(int size)
{
vertices_ = vector<Vertex>(size);
}
+// At present, we do not need this debugging code, but
+// I am going to leave it here in case we need it again.
+#if 0
void Graph::dumpGraph() const
{
vector<Vertex>::const_iterator it = vertices_.begin();
std::vector<Arrow *>::const_iterator iit = it->in_arrows.begin();
std::vector<Arrow *>::const_iterator ien = it->in_arrows.end();
for (; iit != ien; ++iit)
- LYXERR0("From " << (*iit)->from << " to " << (*iit)->to
- << ". Marked: " << (*iit)->marked);
+ LYXERR0("From " << (*iit)->from << " to " << (*iit)->to);
LYXERR0("Out arrows...");
iit = it->out_arrows.begin();
ien = it->out_arrows.end();
for (; iit != ien; ++iit)
- LYXERR0("From " << (*iit)->from << " to " << (*iit)->to
- << ". Marked: " << (*iit)->marked);
+ LYXERR0("From " << (*iit)->from << " to " << (*iit)->to);
}
}
+#endif
} // namespace lyx