[Lemon-commits] [lemon_svn] jacint: r46 - hugo/trunk/src/work
Lemon SVN
svn at lemon.cs.elte.hu
Mon Nov 6 20:37:00 CET 2006
Author: jacint
Date: Fri Jan 23 23:26:13 2004
New Revision: 46
Added:
hugo/trunk/src/work/dijkstra.hh
hugo/trunk/src/work/flow_test.cc
hugo/trunk/src/work/jacint_makefile
Log:
Primitive Dijkstra with stl priority queue. flow_test.cc is for testing flows and Dijkstra.
Added: hugo/trunk/src/work/dijkstra.hh
==============================================================================
--- (empty file)
+++ hugo/trunk/src/work/dijkstra.hh Fri Jan 23 23:26:13 2004
@@ -0,0 +1,192 @@
+/*
+ *dijkstra
+ *by jacint
+ *Performs Dijkstra's algorithm from node s.
+ *
+ *Constructor:
+ *
+ *dijkstra(graph_type& G, node_iterator s, edge_property_vector& distance)
+ *
+ *
+ *
+ *Member functions:
+ *
+ *void run()
+ *
+ * The following function should be used after run() was already run.
+ *
+ *
+ *T dist(node_iterator v) : returns the distance from s to v.
+ * It is 0 if v is not reachable from s.
+ *
+ *
+ *edge_iterator pred(node_iterator v)
+ * Returns the last edge of a shortest s-v path.
+ * Returns an invalid iterator if v=s or v is not
+ * reachable from s.
+ *
+ *
+ *bool reach(node_iterator v) : true if v is reachable from s
+ *
+ *
+ *
+ *
+ *
+ *Problems:
+ *
+ *Heap implementation is needed, because the priority queue of stl
+ *does not have a mathod for key-decrease, so we had to use here a
+ *g\'any solution.
+ *
+ *The implementation of infinity would be desirable, see after line 100.
+ */
+
+#ifndef DIJKSTRA_HH
+#define DIJKSTRA_HH
+
+#include <queue>
+#include <algorithm>
+
+#include <marci_graph_traits.hh>
+#include <marci_property_vector.hh>
+
+
+namespace std {
+ namespace marci {
+
+
+
+
+
+ template <typename graph_type, typename T>
+ class dijkstra{
+ typedef typename graph_traits<graph_type>::node_iterator node_iterator;
+ typedef typename graph_traits<graph_type>::edge_iterator edge_iterator;
+ typedef typename graph_traits<graph_type>::each_node_iterator each_node_iterator;
+ typedef typename graph_traits<graph_type>::in_edge_iterator in_edge_iterator;
+ typedef typename graph_traits<graph_type>::out_edge_iterator out_edge_iterator;
+
+
+ graph_type& G;
+ node_iterator s;
+ node_property_vector<graph_type, edge_iterator> predecessor;
+ node_property_vector<graph_type, T> distance;
+ edge_property_vector<graph_type, T> length;
+ node_property_vector<graph_type, bool> reached;
+
+ public :
+
+ /*
+ The distance of all the nodes is 0.
+ */
+ dijkstra(graph_type& _G, node_iterator _s, edge_property_vector<graph_type, T>& _length) :
+ G(_G), s(_s), predecessor(G, 0), distance(G, 0), length(_length), reached(G, false) { }
+
+
+
+ /*By Misi.*/
+ struct node_dist_comp
+ {
+ node_property_vector<graph_type, T> &d;
+ node_dist_comp(node_property_vector<graph_type, T> &_d) : d(_d) {}
+
+ bool operator()(const node_iterator& u, const node_iterator& v) const
+ { return d.get(u) < d.get(v); }
+ };
+
+
+
+ void run() {
+
+ node_property_vector<graph_type, bool> scanned(G, false);
+ std::priority_queue<node_iterator, vector<node_iterator>, node_dist_comp>
+ heap(( node_dist_comp(distance) ));
+
+ heap.push(s);
+ reached.put(s, true);
+
+ while (!heap.empty()) {
+
+ node_iterator v=heap.top();
+ heap.pop();
+
+
+ if (!scanned.get(v)) {
+
+ for(out_edge_iterator e=G.first_out_edge(v); e.valid(); ++e) {
+ node_iterator w=G.head(e);
+
+ if (!scanned.get(w)) {
+ if (!reached.get(w)) {
+ reached.put(w,true);
+ distance.put(w, distance.get(v)-length.get(e));
+ predecessor.put(w,e);
+ } else if (distance.get(v)-length.get(e)>distance.get(w)) {
+ distance.put(w, distance.get(v)-length.get(e));
+ predecessor.put(w,e);
+ }
+
+ heap.push(w);
+
+ }
+
+ }
+ scanned.put(v,true);
+
+ } // if (!scanned.get(v))
+
+
+
+ } // while (!heap.empty())
+
+
+ } //void run()
+
+
+
+
+
+ /*
+ *Returns the distance of the node v.
+ *It is 0 for the root and for the nodes not
+ *reachable form the root.
+ */
+ T dist(node_iterator v) {
+ return -distance.get(v);
+ }
+
+
+
+ /*
+ * Returns the last edge of a shortest s-v path.
+ * Returns an invalid iterator if v=root or v is not
+ * reachable from the root.
+ */
+ edge_iterator pred(node_iterator v) {
+ if (v!=s) { return predecessor.get(v);}
+ else {return edge_iterator();}
+ }
+
+
+
+ bool reach(node_iterator v) {
+ return reached.get(v);
+ }
+
+
+
+
+
+
+
+
+
+ };// class dijkstra
+
+
+
+ } // namespace marci
+}
+#endif //DIJKSTRA_HH
+
+
Added: hugo/trunk/src/work/flow_test.cc
==============================================================================
--- (empty file)
+++ hugo/trunk/src/work/flow_test.cc Fri Jan 23 23:26:13 2004
@@ -0,0 +1,247 @@
+#include <iostream>
+#include <vector>
+#include <string>
+
+#include <marci_list_graph.hh>
+#include <marci_graph_traits.hh>
+#include <marci_property_vector.hh>
+#include <preflow_push_hl.hh>
+#include <preflow_push_max_flow.hh>
+#include <reverse_bfs.hh>
+#include <dijkstra.hh>
+
+using namespace marci;
+
+
+int main (int, char*[])
+{
+ typedef graph_traits<list_graph>::node_iterator node_iterator;
+ typedef graph_traits<list_graph>::edge_iterator edge_iterator;
+ typedef graph_traits<list_graph>::each_node_iterator each_node_iterator;
+ typedef graph_traits<list_graph>::each_edge_iterator each_edge_iterator;
+ typedef graph_traits<list_graph>::out_edge_iterator out_edge_iterator;
+ typedef graph_traits<list_graph>::in_edge_iterator in_edge_iterator;
+ typedef graph_traits<list_graph>::sym_edge_iterator sym_edge_iterator;
+
+ list_graph flow_test;
+
+ //Ahuja könyv példája, maxflowvalue=13
+ node_iterator s=flow_test.add_node();
+ node_iterator v1=flow_test.add_node();
+ node_iterator v2=flow_test.add_node();
+ node_iterator v3=flow_test.add_node();
+ node_iterator v4=flow_test.add_node();
+ node_iterator v5=flow_test.add_node();
+ node_iterator t=flow_test.add_node();
+
+ node_property_vector<list_graph, std::string> node_name(flow_test);
+ node_name.put(s, "s");
+ node_name.put(v1, "v1");
+ node_name.put(v2, "v2");
+ node_name.put(v3, "v3");
+ node_name.put(v4, "v4");
+ node_name.put(v5, "v5");
+ node_name.put(t, "t");
+
+ edge_iterator s_v1=flow_test.add_edge(s, v1);
+ edge_iterator s_v2=flow_test.add_edge(s, v2);
+ edge_iterator s_v3=flow_test.add_edge(s, v3);
+ edge_iterator v2_v4=flow_test.add_edge(v2, v4);
+ edge_iterator v2_v5=flow_test.add_edge(v2, v5);
+ edge_iterator v3_v5=flow_test.add_edge(v3, v5);
+ edge_iterator v4_t=flow_test.add_edge(v4, t);
+ edge_iterator v5_t=flow_test.add_edge(v5, t);
+ edge_iterator v2_s=flow_test.add_edge(v2, s);
+
+ edge_property_vector<list_graph, int> cap(flow_test);
+ cap.put(s_v1, 0);
+ cap.put(s_v2, 10);
+ cap.put(s_v3, 10);
+ cap.put(v2_v4, 5);
+ cap.put(v2_v5, 8);
+ cap.put(v3_v5, 5);
+ cap.put(v4_t, 8);
+ cap.put(v5_t, 8);
+ cap.put(v2_s, 0);
+
+
+
+ //Marci példája, maxflowvalue=23
+ /* node_iterator s=flow_test.add_node();
+ node_iterator v1=flow_test.add_node();
+ node_iterator v2=flow_test.add_node();
+ node_iterator v3=flow_test.add_node();
+ node_iterator v4=flow_test.add_node();
+ node_iterator t=flow_test.add_node();
+ node_iterator w=flow_test.add_node();
+
+
+ node_property_vector<list_graph, std::string> node_name(flow_test);
+ node_name.put(s, "s");
+ node_name.put(v1, "v1");
+ node_name.put(v2, "v2");
+ node_name.put(v3, "v3");
+ node_name.put(v4, "v4");
+ node_name.put(t, "t");
+ node_name.put(w, "w");
+
+ edge_iterator s_v1=flow_test.add_edge(s, v1);
+ edge_iterator s_v2=flow_test.add_edge(s, v2);
+ edge_iterator v1_v2=flow_test.add_edge(v1, v2);
+ edge_iterator v2_v1=flow_test.add_edge(v2, v1);
+ edge_iterator v1_v3=flow_test.add_edge(v1, v3);
+ edge_iterator v3_v2=flow_test.add_edge(v3, v2);
+ edge_iterator v2_v4=flow_test.add_edge(v2, v4);
+ edge_iterator v4_v3=flow_test.add_edge(v4, v3);
+ edge_iterator v3_t=flow_test.add_edge(v3, t);
+ edge_iterator v4_t=flow_test.add_edge(v4, t);
+ edge_iterator v3_v3=flow_test.add_edge(v3, v3);
+ edge_iterator s_w=flow_test.add_edge(s, w);
+ // edge_iterator v2_s=flow_test.add_edge(v2, s);
+
+
+
+ edge_property_vector<list_graph, int> cap(flow_test); //serves as length in dijkstra
+ cap.put(s_v1, 16);
+ cap.put(s_v2, 13);
+ cap.put(v1_v2, 10);
+ cap.put(v2_v1, 4);
+ cap.put(v1_v3, 12);
+ cap.put(v3_v2, 9);
+ cap.put(v2_v4, 14);
+ cap.put(v4_v3, 7);
+ cap.put(v3_t, 20);
+ cap.put(v4_t, 4);
+ cap.put(v3_v3, 4);
+ cap.put(s_w, 4);
+ // cap.put(v2_s, 0);
+
+*/
+
+ //pelda 3, maxflowvalue=4
+ /* node_iterator s=flow_test.add_node();
+ node_iterator v1=flow_test.add_node();
+ node_iterator v2=flow_test.add_node();
+ node_iterator t=flow_test.add_node();
+ node_iterator w=flow_test.add_node();
+
+ node_property_vector<list_graph, std::string> node_name(flow_test);
+ node_name.put(s, "s");
+ node_name.put(v1, "v1");
+ node_name.put(v2, "v2");
+ node_name.put(t, "t");
+ node_name.put(w, "w");
+
+ edge_iterator s_v1=flow_test.add_edge(s, v1);
+ edge_iterator v1_v2=flow_test.add_edge(v1, v2);
+ edge_iterator v2_t=flow_test.add_edge(v2, t);
+ edge_iterator v1_v1=flow_test.add_edge(v1, v1);
+ edge_iterator s_w=flow_test.add_edge(s, w);
+
+
+ edge_property_vector<list_graph, int> cap(flow_test);
+
+ cap.put(s_v1, 16);
+ cap.put(v1_v2, 10);
+ cap.put(v2_t, 4);
+ cap.put(v1_v1, 3);
+ cap.put(s_w, 5);
+ */
+
+
+
+
+ std::cout << "Testing reverse_bfs..." << std::endl;
+
+ reverse_bfs<list_graph> bfs_test(flow_test, t);
+
+ bfs_test.run();
+
+ for (each_node_iterator w=flow_test.first_node(); w.valid(); ++w) {
+ std::cout <<"The distance of " << w << " is " << bfs_test.dist(w) <<std::endl;
+ }
+
+
+
+
+
+ std::cout << "Testing preflow_push_hl..." << std::endl;
+
+ preflow_push_hl<list_graph, int> preflow_push_test(flow_test, s, t, cap);
+
+ preflow_push_test.run();
+
+ std::cout << "Maximum flow value is: " << preflow_push_test.maxflow() << "."<<std::endl;
+
+ std::cout<< "The flow on edge s-v1 is "<< preflow_push_test.flowonedge(s_v1) << "."<<std::endl;
+
+ edge_property_vector<list_graph, int> flow=preflow_push_test.allflow();
+ for (each_edge_iterator e=flow_test.first_edge(); e.valid(); ++e) {
+ std::cout <<"Flow on edge " << flow_test.tail(e) <<"-" << flow_test.head(e)<< " is " <<flow.get(e) <<std::endl;
+ }
+
+ std::cout << "A minimum cut: " <<std::endl;
+ node_property_vector<list_graph, bool> mincut=preflow_push_test.mincut();
+
+ for (each_node_iterator v=flow_test.first_node(); v.valid(); ++v) {
+ if (mincut.get(v)) std::cout <<node_name.get(v)<< " ";
+ }
+
+ std::cout<<"\n\n"<<std::endl;
+
+
+
+
+ std::cout << "Testing preflow_push_max_flow..." << std::endl;
+
+ preflow_push_max_flow<list_graph, int> max_flow_test(flow_test, s, t, cap);
+
+ max_flow_test.run();
+
+ std::cout << "Maximum flow value is: " << max_flow_test.maxflow() << "."<< std::endl;
+
+ std::cout << "A minimum cut: " <<std::endl;
+ node_property_vector<list_graph, bool> mincut2=max_flow_test.mincut();
+
+ for (each_node_iterator v=flow_test.first_node(); v.valid(); ++v) {
+ if (mincut2.get(v)) std::cout <<node_name.get(v)<< " ";
+ }
+
+ std::cout << std::endl <<std::endl;
+
+
+
+ std::cout << "Testing dijkstra..." << std::endl;
+
+ node_iterator root=v2;
+
+ dijkstra<list_graph, int> dijkstra_test(flow_test, root, cap);
+
+ dijkstra_test.run();
+
+ for (each_node_iterator w=flow_test.first_node(); w.valid(); ++w) {
+ if (dijkstra_test.reach(w)) {
+ std::cout <<"The distance of " << w << " is " << dijkstra_test.dist(w);
+ if (dijkstra_test.pred(w).valid()) {
+ std::cout <<", a shortest path from the root ends with edge " << dijkstra_test.pred(w) <<std::endl;
+ } else {
+ std::cout <<", this is the root."<<std::endl; }
+
+ } else {
+ cout << w << " is not reachable from " << root <<std::endl;
+ }
+ }
+
+
+
+ return 0;
+}
+
+
+
+
+
+
+
+
+
Added: hugo/trunk/src/work/jacint_makefile
==============================================================================
--- (empty file)
+++ hugo/trunk/src/work/jacint_makefile Fri Jan 23 23:26:13 2004
@@ -0,0 +1,9 @@
+CCFLAGS = -Wall -ansi
+CXXFLAGS = -Wall -ansi -I. -g
+CC = g++-3.0
+
+flow_test: flow_test.cc marci_list_graph.hh reverse_bfs.hh preflow_push_hl.hh marci_graph_traits.hh marci_property_vector.hh preflow_push_max_flow.hh dijkstra.hh
+ $(CXX) $(CXXFLAGS) -o flow_test flow_test.cc
+
+marci_graph_demo: marci_graph_demo.cc marci_graph_traits.hh marci_list_graph.hh marci_property_vector.hh marci_bfs.hh marci_max_flow.hh
+ $(CC) $(CCFLAGS) -I. marci_graph_demo.cc -o marci_graph_demo
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