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Create getter method for the SCC collection

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stefiosif
2022-09-29 23:32:25 +03:00
parent f4acf57c88
commit 9fd41bd85b
1 changed files with 12 additions and 10 deletions
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22
algorithm/roditty_zwick.h
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@@ -28,6 +28,8 @@ public:
// Remove edge (u,v) and update A accordingly for fast checking query
void remove(const T& u, const T& v) override;
std::map<T, SCC<T>> getSCCs() { return C; }
void setGraph(Digraph<T> G);
private:
// Array used to answer strong connectivity queries in O(1) time
@@ -37,8 +39,8 @@ private:
std::map<T, SCC<T>> C;
// Maintain in-out bfs trees
std::map<T, BreadthFirstTree<T>> inTree;
std::map<T, BreadthFirstTree<T>> outTree;
std::map<T, BreadthFirstTree<T>> In;
std::map<T, BreadthFirstTree<T>> Out;
};
template<typename T>
@@ -53,11 +55,11 @@ void RodittyZwick<T>::findSCC() {
for (auto& SCC : SCCs) {
const auto& w = SCC.id;
for (const auto& v : std::views::keys(SCC.adjMatrix))
for (const auto& v : SCC.vertices())
A[v] = w;
outTree[w] = BreadthFirstTree<T>(SCC, w);
inTree[w] = BreadthFirstTree<T>(SCC.reverse(), w);
Out[w] = BreadthFirstTree<T>(SCC, w);
In[w] = BreadthFirstTree<T>(SCC.reverse(), w);
C[w] = SCC;
}
@@ -78,16 +80,16 @@ void RodittyZwick<T>::remove(const T& u, const T& v) {
if (A[u] != A[v]) return;
// If edge (u,v) is not contained in both inTree and outTree do nothing
if (!inTree[w].adjMatrix[u].contains(v) &&
!outTree[w].adjMatrix[u].contains(v))
if (!In[w].adjMatrix[u].contains(v) &&
!Out[w].adjMatrix[u].contains(v))
return;
// Update In(w) and Out(w)
outTree[w] = BreadthFirstTree<T>(C[w], w);
inTree[w] = BreadthFirstTree<T>(C[w].reverse(), w);
Out[w] = BreadthFirstTree<T>(C[w], w);
In[w] = BreadthFirstTree<T>(C[w].reverse(), w);
// If a SCC is broken, compute all SCCs again
if (!inTree[w].adjMatrix.count(u) || !outTree[w].adjMatrix.count(v))
if (!In[w].adjMatrix.count(u) || !Out[w].adjMatrix.count(v))
findSCC();
}