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Merge branch 'Zhdanovich-scc_develop' into develop

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Dennis Luxen 2014-07-30 09:42:55 +02:00
commit e1d94eee21
1 changed files with 16 additions and 8 deletions
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22
Algorithms/StronglyConnectedComponents.h
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@ -228,7 +228,7 @@ class TarjanSCC
TIMER_START(SCC_RUN); TIMER_START(SCC_RUN);
// The following is a hack to distinguish between stuff that happens // The following is a hack to distinguish between stuff that happens
// before the recursive call and stuff that happens after // before the recursive call and stuff that happens after
std::stack<std::pair<bool, TarjanStackFrame>> recursion_stack; std::stack<TarjanStackFrame> recursion_stack;
// true = stuff before, false = stuff after call // true = stuff before, false = stuff after call
std::stack<NodeID> tarjan_stack; std::stack<NodeID> tarjan_stack;
std::vector<unsigned> components_index(m_node_based_graph->GetNumberOfNodes(), std::vector<unsigned> components_index(m_node_based_graph->GetNumberOfNodes(),
@ -237,25 +237,32 @@ class TarjanSCC
std::vector<TarjanNode> tarjan_node_list(m_node_based_graph->GetNumberOfNodes()); std::vector<TarjanNode> tarjan_node_list(m_node_based_graph->GetNumberOfNodes());
unsigned component_index = 0, size_of_current_component = 0; unsigned component_index = 0, size_of_current_component = 0;
int index = 0; int index = 0;
NodeID last_node = m_node_based_graph->GetNumberOfNodes(); const NodeID last_node = m_node_based_graph->GetNumberOfNodes();
std::vector<bool> processing_node_before_recursion(m_node_based_graph->GetNumberOfNodes(), true);
for(const NodeID node : boost::irange(0u, last_node)) for(const NodeID node : boost::irange(0u, last_node))
{ {
if (SPECIAL_NODEID == components_index[node]) if (SPECIAL_NODEID == components_index[node])
{ {
recursion_stack.emplace(true, TarjanStackFrame(node, node)); recursion_stack.emplace(TarjanStackFrame(node, node));
} }
while (!recursion_stack.empty()) while (!recursion_stack.empty())
{ {
const bool before_recursion = recursion_stack.top().first; TarjanStackFrame currentFrame = recursion_stack.top();
TarjanStackFrame currentFrame = recursion_stack.top().second;
const NodeID v = currentFrame.v; const NodeID v = currentFrame.v;
recursion_stack.pop(); recursion_stack.pop();
const bool before_recursion = processing_node_before_recursion[v];
if (before_recursion && tarjan_node_list[v].index != UINT_MAX)
{
continue;
}
if (before_recursion) if (before_recursion)
{ {
// Mark frame to handle tail of recursion // Mark frame to handle tail of recursion
recursion_stack.emplace(false, currentFrame); recursion_stack.emplace(currentFrame);
processing_node_before_recursion[v] = false;
// Mark essential information for SCC // Mark essential information for SCC
tarjan_node_list[v].index = index; tarjan_node_list[v].index = index;
@ -271,7 +278,7 @@ class TarjanSCC
m_node_based_graph->GetTarget(current_edge); m_node_based_graph->GetTarget(current_edge);
if (SPECIAL_NODEID == tarjan_node_list[vprime].index) if (SPECIAL_NODEID == tarjan_node_list[vprime].index)
{ {
recursion_stack.emplace(true, TarjanStackFrame(vprime, v)); recursion_stack.emplace(TarjanStackFrame(vprime, v));
} }
else else
{ {
@ -285,6 +292,7 @@ class TarjanSCC
} }
else else
{ {
processing_node_before_recursion[v] = true;
tarjan_node_list[currentFrame.parent].low_link = tarjan_node_list[currentFrame.parent].low_link =
std::min(tarjan_node_list[currentFrame.parent].low_link, std::min(tarjan_node_list[currentFrame.parent].low_link,
tarjan_node_list[v].low_link); tarjan_node_list[v].low_link);