Refactor: Change reachability interfaces to handle multiple removals/insertions

include/algorithm/decremental_reachability.h

@@ -18,7 +18,7 @@ public:
   virtual bool query(const T& u, const T& v) =0;
 
   // Remove edge e(u,v) and maintain the transitive closure matrix
-  virtual void remove(const T& u, const T& v) =0;
+  virtual void remove(const std::vector<std::pair<T, T>>& edges) =0;
 protected:
   Digraph<T> G;
 };

include/algorithm/dynamic_reachability.h

@@ -9,7 +9,7 @@ template<typename T>
 class DynamicReachability : public DecrementalReachability<T> {
 
   // Insert edge e(u,v) and maintain the transitive closure matrix
-  virtual void insert(const T& u, const T& v) =0;
+  virtual void insert(const T& c, const std::vector<T>& vertices) =0;
 };
 
 

include/algorithm/frigioni.h

@@ -24,11 +24,8 @@ public:
   // in O(1) using the transitive closure matrix
   bool query(const T& u, const T& v) override;
 
-  // Delete edge e(u, v)
-  void remove(const T& u, const T& v) override;
-
   // Delete set of edges and explicitely maintain the transitive closure
-  void remove(const std::vector<std::pair<T, T>>& edges);
+  void remove(const std::vector<std::pair<T, T>>& edges) override;
 private:
   // Transitive closure matrix, used to answer reachability queries in O(1)
   std::unordered_map<T, std::unordered_map<T, bool>> TC;
@@ -84,11 +81,6 @@ bool Frigioni<T>::query(const T& u, const T& v) {
   return TC[u][v];
 }
 
-template<typename T>
-void Frigioni<T>::remove(const T& u, const T& v) {
-  
-}
-
 template<typename T>
 void Frigioni<T>::remove(const std::vector<std::pair<T, T>>& edges) {
   std::vector<std::pair<T, T>> Eint;

include/algorithm/henzinger_king.h

@@ -25,16 +25,10 @@ public:
   // and then if necessary check the set S
   bool query(const T& u, const T& v) override;
 
-  // Delete edge e(u, v)
-  void remove(const T& u, const T& v) override;
-
   // Remove collection of edges from the decremental maintenance data structure
   // and for every vertex in set S, rebuilt reachability trees from scratch
   void remove(const std::vector<std::pair<T,T>>& edges);
 
-  // Add edge e(u, v)
-  void insert(const T& u, const T& v) override;
-
   // Insert collection of edges in set S, if threshold is reached re-initialize
   // algorithm, otherwise construct reachability trees for the vertex that is
   // the center-of-insertions
@@ -70,15 +64,10 @@ bool HenzingerKing<T>::query(const T& u, const T& v) {
                      });
 }
 
-template<typename T>
-void HenzingerKing<T>::remove(const T& u, const T& v) {
-  this->G.remove(u, v);
-}
-
 template<typename T>
 void HenzingerKing<T>::remove(const std::vector<std::pair<T, T>>& edges) {
   for (const auto& [u, v] : edges) {
-    remove(u, v);
+    this->G.remove(u, v);
   }
   frigioni.remove(edges);
 
@@ -88,15 +77,10 @@ void HenzingerKing<T>::remove(const std::vector<std::pair<T, T>>& edges) {
   }
 }
 
-template<typename T>
-void HenzingerKing<T>::insert(const T& u, const T& v) {
-  this->G.insert(u, v);
-}
-
 template<typename T>
 void HenzingerKing<T>::insert(const T& c, const std::vector<T>& vertices) {
   for (const auto& w : vertices)
-    insert(c, w);
+    this->G.insert(c, w);
 
   S.insert(c);
   if (S.size() > threshold) {

include/algorithm/italiano.h

@@ -24,8 +24,11 @@ public:
   // in O(1) using the transitive closure matrix
   bool query(const T& u, const T& v) override;
 
+  // Delete collection of edges
+  void remove(const std::vector<std::pair<T, T>>& edges) override;
+
   // Delete edge e(u, v) and explicitely maintain the transitive closure
-  void remove(const T& u, const T& v) override;
+  void remove(const T& u, const T& v);
 private:
   // Transitive closure matrix
   std::unordered_map<T, std::unordered_map<T, bool>> TC;
@@ -64,6 +67,12 @@ bool Italiano<T>::query(const T& u, const T& v) {
   return TC[u][v];
 }
 
+template<typename T>
+void Italiano<T>::remove(const std::vector<std::pair<T, T>>& edges) {
+  for (const auto& [u, v] : edges)
+    remove(u, v);
+}
+
 template<typename T>
 void Italiano<T>::remove(const T& u, const T& v) {
   if (!this->G.adjList[u].contains(v)) return;

include/algorithm/king.h

@@ -23,12 +23,15 @@ public:
   // in O(n) using the stored decremental maintenance data structure for DAGs
   bool query(const T& u, const T& v) override;
 
+  // Delete collection of edges
+  void remove(const std::vector<std::pair<T, T>>& edges) override;
+
   // Delete edge e(u, v) from all reachability trees and update each one of
   // them using the decremental reachability algorithm for DAGs
-  void remove(const T& u, const T& v) override;
+  void remove(const T& u, const T& v);
 
   // Insert edge e(u, v) by reconstructing all reachability trees
-  void insert(const T& u, const T& v) override;
+  void insert(const T& c, const std::vector<T>& vertices) override;
 private:
   // Connect each reachabiliy tree with decremental maintenance data structure
   std::unordered_map<T, Italiano<T>> In;
@@ -53,6 +56,12 @@ bool King<T>::query(const T& u, const T& v) {
                      });
 }
 
+template<typename T>
+void King<T>::remove(const std::vector<std::pair<T, T>>& edges) {
+  for (const auto& [u, v] : edges)
+    remove(u, v);
+}
+
 template<typename T>
 void King<T>::remove(const T& u, const T& v) {
   this->G.remove(u, v);
@@ -63,8 +72,9 @@ void King<T>::remove(const T& u, const T& v) {
 }
 
 template<typename T>
-void King<T>::insert(const T& u, const T& v) {
-  this->G.insert(u, v);
+void King<T>::insert(const T& c, const std::vector<T>& vertices) {
+  for (const auto& v : vertices)
+    this->G.insert(c, v);
   init();
 }
 

include/algorithm/roditty_zwick.h

@@ -25,8 +25,11 @@ public:
   // Return true if u and v are in the same SCC
   bool query(const T& u, const T& v) override;
 
+  // Delete collection of edges
+  void remove(const std::vector<std::pair<T, T>>& edges) override;
+
   // Remove edge (u,v) and update A accordingly for fast checking query
-  void remove(const T& u, const T& v) override;
+  void remove(const T& u, const T& v);
 
   std::unordered_map<T, SCC<T>> getSCCs() { return C; }
 private:
@@ -68,6 +71,12 @@ bool RodittyZwick<T>::query(const T& u, const T& v) {
   return A[u] == A[v];
 }
 
+template<typename T>
+void RodittyZwick<T>::remove(const std::vector<std::pair<T, T>>& edges) {
+  for (const auto& [u, v] : edges)
+    remove(u, v);
+}
+
 template<typename T>
 void RodittyZwick<T>::remove(const T& u, const T& v) {
   const auto& w = A[u];

test/dynamic_reachability_test.cc

@@ -60,7 +60,7 @@ TEST_SUITE("Dynamic Reachability Test") {
     }
 
     SUBCASE("King::insert") {
-      king.insert(3, 10);
+      king.insert(3, { 10 });
 
       CHECK_EQ(king.query(1, 10), true);
       CHECK_EQ(king.query(2, 10), false);