examples: C++11: Some use of range-based for loop.

Author: murraycu

example/cuthill_mckee_ordering.cpp

@@ -56,8 +56,8 @@ int main(int , char* [])
                      Pair(6,7) }; //g-h 
 
   Graph G(10);
-  for (int i = 0; i < 14; ++i)
-    add_edge(edges[i].first, edges[i].second, G);
+  for (const auto& edge : edges)
+    add_edge(edge.first, edge.second, G);
 
   graph_traits<Graph>::vertex_iterator ui, ui_end;
 
@@ -78,9 +78,8 @@ int main(int , char* [])
                            get(vertex_degree, G));
     cout << "Reverse Cuthill-McKee ordering starting at: " << s << endl;
     cout << "  ";    
-    for (auto i = inv_perm.begin();
-         i != inv_perm.end(); ++i)
-      cout << index_map[*i] << " ";
+    for (const auto& vertex : inv_perm)
+      cout << index_map[vertex] << " ";
     cout << endl;
 
     for (size_type c = 0; c != inv_perm.size(); ++c)
@@ -96,9 +95,8 @@ int main(int , char* [])
                            get(vertex_degree, G));
     cout << "Reverse Cuthill-McKee ordering starting at: " << s << endl;
     cout << "  ";
-    for (auto i=inv_perm.begin();
-       i != inv_perm.end(); ++i)
-      cout << index_map[*i] << " ";
+    for (const auto& vertex : inv_perm)
+      cout << index_map[vertex] << " ";
     cout << endl;
 
     for (size_type c = 0; c != inv_perm.size(); ++c)
@@ -115,9 +113,8 @@ int main(int , char* [])
 
     cout << "Reverse Cuthill-McKee ordering:" << endl;
     cout << "  ";
-    for (auto i=inv_perm.begin();
-       i != inv_perm.end(); ++i)
-      cout << index_map[*i] << " ";
+    for (const auto& vertex : inv_perm)
+      cout << index_map[vertex] << " ";
     cout << endl;
 
     for (size_type c = 0; c != inv_perm.size(); ++c)

example/edge-connectivity.cpp

@@ -126,12 +126,12 @@ namespace boost
     }
 
     std::vector < bool > in_S_star(num_vertices(g), false);
-    for (auto si = S_star.begin(); si != S_star.end(); ++si)
-      in_S_star[*si] = true;
+    for (const auto& vertex : S_star.begin())
+      in_S_star[vertex] = true;
     degree_size_type c = 0;
-    for (auto si = S_star.begin(); si != S_star.end(); ++si) {
+    for (const auto& vertex : S_star.begin()) {
       typename graph_traits < VertexListGraph >::out_edge_iterator ei, ei_end;
-      for (boost::tie(ei, ei_end) = out_edges(*si, g); ei != ei_end; ++ei)
+      for (boost::tie(ei, ei_end) = out_edges(vertex, g); ei != ei_end; ++ei)
         if (!in_S_star[target(*ei, g)]) {
           *disconnecting_set++ = *ei;
           ++c;
@@ -159,11 +159,10 @@ main()
   auto attr_map = get(vertex_attribute, g);
 
   std::cout << "The disconnecting set is {";
-  for (auto i =
-       disconnecting_set.begin(); i != disconnecting_set.end(); ++i)
+  for (const auto& edge : disconnecting_set)
     std::
-      cout << "(" << attr_map[source(*i, g)]["label"] << "," <<
-      attr_map[target(*i, g)]["label"] << ") ";
+      cout << "(" << attr_map[source(edge, g)]["label"] << "," <<
+      attr_map[target(edge, g)]["label"] << ") ";
   std::cout << "}." << std::endl;
   return EXIT_SUCCESS;
 }

example/king_ordering.cpp

@@ -96,9 +96,8 @@ int main(int , char* [])
                   get(vertex_degree, G), get(vertex_index, G));
     cout << "King ordering starting at: " << s << endl;
     cout << "  ";
-    for (auto i=inv_perm.begin();
-       i != inv_perm.end(); ++i)
-      cout << index_map[*i] << " ";
+    for (const auto& vertex : inv_perm)
+      cout << index_map[vertex] << " ";
     cout << endl;
 
     for (size_type c = 0; c != inv_perm.size(); ++c)
@@ -115,9 +114,8 @@ int main(int , char* [])
 
     cout << "King ordering:" << endl;
     cout << "  ";
-    for (auto i=inv_perm.begin();
-       i != inv_perm.end(); ++i)
-      cout << index_map[*i] << " ";
+    for (const auto& vertex : inv_perm)
+      cout << index_map[vertex] << " ";
     cout << endl;
 
     for (size_type c = 0; c != inv_perm.size(); ++c)

example/kruskal-telephone.cpp

@@ -36,13 +36,13 @@ main()
 
   auto weight = get(edge_weight, g);
   int total_weight = 0;
-  for (size_type e = 0; e < mst.size(); ++e)
-    total_weight += get(weight, mst[e]);
+  for (const auto& edge : mst)
+    total_weight += get(weight, edge);
   std::cout << "total weight: " << total_weight << std::endl;
 
   typedef graph_traits < Graph >::vertex_descriptor Vertex;
-  for (size_type i = 0; i < mst.size(); ++i) {
-    auto u = source(mst[i], g), v = target(mst[i], g);
+  for (const auto& edge : mst) {
+    auto u = source(edge, g), v = target(edge, g);
     edge_attr_map[edge(u, v, g_dot).first]["color"] = "black";
   }
   std::ofstream out("figs/telephone-mst-kruskal.dot");

example/matching_example.cpp

@@ -76,8 +76,8 @@ int main()
 
   std::cout << "In the following graph:" << std::endl << std::endl;
 
-  for (auto itr = ascii_graph.begin(); itr != ascii_graph.end(); ++itr)
-    std::cout << *itr << std::endl;
+  for (const auto& str : ascii_graph)
+    std::cout << str << std::endl;
 
   std::cout << std::endl << "Found a matching of size " << matching_size(g, &mate[0]) << std::endl;
 

example/topo-sort1.cpp

@@ -41,10 +41,8 @@ main()
   topological_sort(g, std::front_inserter(topo_order),
                    vertex_index_map(identity_property_map()));
 
-  int n = 1;
-  for (auto i = topo_order.begin();
-       i != topo_order.end(); ++i, ++n)
-    std::cout << tasks[*i] << std::endl;
+  for (const auto& vertex : topo_order)
+    std::cout << tasks[vertex] << std::endl;
 
   return EXIT_SUCCESS;
 }

example/topo-sort2.cpp

@@ -41,10 +41,8 @@ main()
   topological_sort(g, std::front_inserter(topo_order),
                    vertex_index_map(identity_property_map()));
 
-  int n = 1;
-  for (auto i = topo_order.begin();
-       i != topo_order.end(); ++i, ++n)
-    std::cout << tasks[*i] << std::endl;
+  for (const auto& vertex : topo_order)
+    std::cout << tasks[vertex] << std::endl;
 
   return EXIT_SUCCESS;
 }