Make class Graph abstract and make derived classes Digraph and SCC

algorithm/tarjan.h

@@ -1,23 +1,23 @@
 #ifndef TARJAN_H_
 #define TARJAN_H_
 
-#include "graph/graph.h"
-using namespace graph;
+#include "graph/digraph.h"
+#include "graph/scc.h"
 
-#include <algorithm>
-#include <iostream>
-#include <ranges>
 #include <stack>
+#include <vector>
+
+using namespace graph;
 
 namespace algo {
 
 template<typename T>
 class Tarjan {
 public:
-  Tarjan(Graph<T> G) : G(G) {}
+  Tarjan(Digraph<T> G) : G(G) {}
 
   //
-  std::vector<std::vector<T>> run();
+  std::vector<SCC<T>> run();
 
   //
   void strongConnect(const T& v);
@@ -29,48 +29,48 @@ private:
     bool onStack = false;
   };
 
-  Graph<T> G;
+  Digraph<T> G;
   std::stack<T> S;
   std::int16_t index = 0;
-  std::map<T, Payload> vp;
-  std::vector<std::vector<T>> SCCs;
+  std::map<T, Payload> p;
+  std::vector<SCC<T>> SCCs;
 };
 
 template<typename T>
 void Tarjan<T>::strongConnect(const T& v) {
-  vp[v].index = vp[v].lowlink = index++;
-  vp[v].onStack = true;
+  p[v].index = p[v].lowlink = index++;
+  p[v].onStack = true;
   S.push(v);
   
   for (const auto& w : G.adjMatrix[v]) {
-    if (vp[w].index == -1) {
+    if (p[w].index == -1) {
       strongConnect(w);
-      vp[v].lowlink = std::min(vp[v].lowlink, vp[w].lowlink);
-    } else if (vp[w].onStack) {
-      vp[v].lowlink = std::min(vp[v].lowlink, vp[w].index);
+      p[v].lowlink = std::min(p[v].lowlink, p[w].lowlink);
+    } else if (p[w].onStack) {
+      p[v].lowlink = std::min(p[v].lowlink, p[w].index);
     }
   }
 
   // If v is a root node, pop the stack and generate an SCC
-  if (vp[v].lowlink == vp[v].index) {
-    std::vector<T> SCC;
+  if (p[v].lowlink == p[v].index) {
+    //std::vector<T> scc;
+    std::map<T, std::set<T>> scc;
     bool finished = false;
     do {
       const auto w = S.top();
       S.pop();
-      vp[w].onStack = false;
-      SCC.push_back(w);
-      finished = vp[w].index == vp[v].index;
+      p[w].onStack = false;
+      scc[w] = G.adjMatrix[w];
+      finished = p[w].index == p[v].index;
     } while (!finished);
-    SCCs.push_back(SCC);
+    SCCs.push_back(scc);
   }
 }
 
 template<typename T>
-std::vector<std::vector<T>> Tarjan<T>::run() {
-
+std::vector<SCC<T>> Tarjan<T>::run() {
   for (const auto& v : G.vertices) {
-    if (vp[v].index == -1) {
+    if (p[v].index == -1) {
       strongConnect(v);
     }
   }