Splitting code

src/graph.cpp

@@ -0,0 +1,30 @@
+#include <iostream>
+#include <list>
+
+#include "graph.h"
+
+using namespace std;
+
+// Initialize graph
+Graph::Graph(int vertices) {
+    numVertices = vertices;
+    // Note that this is creating 'vertices' number of lists
+    adjLists = new list<int>[vertices];
+    visited = new bool[vertices];
+}
+
+// Add edges
+void Graph::addEdge(int src, int dest) { adjLists[src].push_front(dest); }
+
+// DFS algorithm
+void Graph::DFS(int vertex) {
+    visited[vertex] = true;
+    // Get the list for this particular vertex
+    list<int> adjList = adjLists[vertex];
+
+    cout << vertex << " ";
+
+    list<int>::iterator i;
+    for (i = adjList.begin(); i != adjList.end(); ++i)
+        if (!visited[*i]) DFS(*i);
+}

src/graph.h

@@ -0,0 +1,16 @@
+#include <list>
+
+using namespace std;
+
+class Graph {
+    int numVertices;
+    // Adjlist is a list of lists
+    list<int>* adjLists;
+    bool* visited;
+
+   public:
+    Graph(int V);
+    void addEdge(int src, int dest);
+    void DFS(int vertex);
+};
+

src/main.cpp

@@ -2,64 +2,11 @@
 
 #include <iostream>
 #include <list>
+
+#include "graph.h"
+
 using namespace std;
 
-// Interface for Expr
-class Expr {
-   public:
-    virtual void print() = 0;
-};
-
-class BinaryExpr : public Expr {
-   public:
-    BinaryExpr(Expr* lhs, Expr* rhs) : lhs(lhs), rhs(rhs) {}
-
-    void print() {
-        lhs->print();
-        rhs->print();
-    }
-
-   private:
-    Expr* lhs;
-    Expr* rhs;
-};
-
-class Graph {
-    int numVertices;
-    // Adjlist is a list of lists
-    list<int>* adjLists;
-    bool* visited;
-
-   public:
-    Graph(int V);
-    void addEdge(int src, int dest);
-    void DFS(int vertex);
-};
-
-// Initialize graph
-Graph::Graph(int vertices) {
-    numVertices = vertices;
-    // Note that this is creating 'vertices' number of lists
-    adjLists = new list<int>[vertices];
-    visited = new bool[vertices];
-}
-
-// Add edges
-void Graph::addEdge(int src, int dest) { adjLists[src].push_front(dest); }
-
-// DFS algorithm
-void Graph::DFS(int vertex) {
-    visited[vertex] = true;
-    // Get the list for this particular vertex
-    list<int> adjList = adjLists[vertex];
-
-    cout << vertex << " ";
-
-    list<int>::iterator i;
-    for (i = adjList.begin(); i != adjList.end(); ++i)
-        if (!visited[*i]) DFS(*i);
-}
-
 int main() {
     Graph g(4);
     g.addEdge(0, 1);