// Multi-Tracked Path
+// Takes the graph description file as input and produces a dot file.
+
+// EXAMPLE: ./mtp ./graph2.txt | dot -T pdf -o- | xpdf -
+
// #define VERBOSE
#include <iostream>
class Edge {
public:
- int occupied;
+ int id, occupied;
scalar_t length, work_length;
Vertex *terminal_vertex;
Edge *next, *pred;
public:
int id;
- Edge *first_edge;
+ Edge *root_edge;
scalar_t distance_from_source;
Vertex *pred_vertex;
Edge *pred_edge;
- Vertex() { first_edge = 0; }
+ Vertex() { root_edge = 0; }
inline void add_edge(Edge *e) {
- e->next = first_edge;
+ e->next = root_edge;
e->pred = 0;
- if(first_edge) { first_edge->pred = e; }
- first_edge = e;
+ if(root_edge) { root_edge->pred = e; }
+ root_edge = e;
}
inline void del_edge(Edge *e) {
- if(e == first_edge) { first_edge = e->next; }
+ if(e == root_edge) { root_edge = e->next; }
if(e->pred) { e->pred->next = e->next; }
if(e->next) { e->next->pred = e->pred; }
}
~Graph();
- void find_best_paths();
+ void find_best_paths(int *result_edge_occupation);
void print();
- void print_occupied_edges();
- void dot_print();
};
void Graph::print() {
for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].first_edge; e; e = e->next) {
- cout << n << " -> " << e->terminal_vertex->id << " " << e->length << endl;
- }
- }
-}
-
-void Graph::print_occupied_edges() {
- for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].first_edge; e; e = e->next) {
- if(e->occupied) {
- int a = n, b = e->terminal_vertex->id;
- if(a > b) { int c = a; a = b; b = c; }
- cout << a << " " << b << endl;
- }
- }
- }
-}
-
-void Graph::dot_print() {
- cout << "digraph {" << endl;
- cout << " node[shape=circle];" << endl;
- for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].first_edge; e; e = e->next) {
- int a = n, b = e->terminal_vertex->id;
+ for(Edge *e = vertices[n].root_edge; e; e = e->next) {
+ cout << n << " -> " << e->terminal_vertex->id << " " << e->length;
if(e->occupied) {
- int c = a; a = b; b = c;
- cout << " " << a << " -> " << b << " [style=bold,color=black,label=\"" << -e->length << "\"];" << endl;
- } else {
- cout << " " << a << " -> " << b << " [color=gray,label=\"" << e->length << "\"];" << endl;
+ cout << " *";
}
+ cout << endl;
}
}
- cout << "}" << endl;
}
Graph::Graph(int nb_vrt, int nb_edges,
for(int e = 0; e < nb_edges; e++) {
vertices[from[e]].add_edge(&edge_heap[e]);
edge_heap[e].occupied = 0;
+ edge_heap[e].id = e;
edge_heap[e].length = lengths[e];
edge_heap[e].terminal_vertex = &vertices[to[e]];
}
void Graph::initialize_work_lengths() {
scalar_t length_min = 0;
for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].first_edge; e; e = e->next) {
+ for(Edge *e = vertices[n].root_edge; e; e = e->next) {
length_min = min(e->length, length_min);
}
}
for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].first_edge; e; e = e->next) {
+ for(Edge *e = vertices[n].root_edge; e; e = e->next) {
e->work_length = e->length - length_min;
}
}
void Graph::update_work_length() {
for(int n = 0; n < nb_vertices; n++) {
scalar_t d = vertices[n].distance_from_source;
- for(Edge *e = vertices[n].first_edge; e; e = e->next) {
+ for(Edge *e = vertices[n].root_edge; e; e = e->next) {
e->work_length += d - e->terminal_vertex->distance_from_source;
}
}
#ifdef DEBUG
for(int n = 0; n < nb_vertices; n++) {
- for(Edge *e = vertices[n].first_edge; e; e = e->next) {
+ for(Edge *e = vertices[n].root_edge; e; e = e->next) {
if(e->work_length < 0) {
cerr << "DEBUG error in find_shortest_path: Edge fixed lengths have to be positive."
<< endl;
new_front_size = 0;
for(int f = 0; f < front_size; f++) {
v = front[f];
- for(Edge *e = v->first_edge; e; e = e->next) {
+ for(Edge *e = v->root_edge; e; e = e->next) {
d = v->distance_from_source + e->work_length;
tv = e->terminal_vertex;
if(d < tv->distance_from_source) {
} while(front_size > 0);
}
-void Graph::find_best_paths() {
+void Graph::find_best_paths(int *result_edge_occupation) {
Vertex **front = new Vertex *[nb_vertices];
Vertex **new_front = new Vertex *[nb_vertices];
}
} while(total_length < 0.0);
- // // We put all occupied edges back to their original orientations
- // for(int n = 0; n < nb_vertices; n++) {
- // Vertex *v = &vertices[n];
- // for(Edge *e = v->first_edge; e; e = e->next) {
- // if(e->occupied) {
- // e->terminal_vertex = v->pred_vertex;
- // e->length = - e->length;
- // e->work_length = 0;
- // v->pred_vertex->del_edge(e);
- // v->add_edge(e);
- // }
- // }
- // }
-
-
delete[] front;
delete[] new_front;
+
+ for(int n = 0; n < nb_vertices; n++) {
+ Vertex *v = &vertices[n];
+ for(Edge *e = v->root_edge; e; e = e->next) {
+ result_edge_occupation[e->id] = e->occupied;
+ }
+ }
+}
+
+void find_best_paths(int nb_vertices,
+ int nb_edges, int *ea, int *eb, scalar_t *el,
+ int source, int sink,
+ int *result_edge_occupation) {
+ Graph graph(nb_vertices, nb_edges, ea, eb, el, source, sink);
+ graph.find_best_paths(result_edge_occupation);
+}
+
+void dot_print(int nb_vertices,
+ int nb_edges, int *ea, int *eb, scalar_t *el,
+ int source, int sink,
+ int *edge_occupation) {
+ cout << "digraph {" << endl;
+ cout << " node[shape=circle];" << endl;
+ for(int e = 0; e < nb_edges; e++) {
+ if(edge_occupation[e]) {
+ cout << " " << ea[e] << " -> " << eb[e] << " [style=bold,color=black,label=\"" << el[e] << "\"];" << endl;
+ } else {
+ cout << " " << ea[e] << " -> " << eb[e] << " [color=gray,label=\"" << el[e] << "\"];" << endl;
+ }
+ }
+ cout << "}" << endl;
}
//////////////////////////////////////////////////////////////////////
(*file) >> nb_vertices >> nb_edges;
(*file) >> source >> sink;
- // cout << "INPUT nb_edges " << nb_edges << endl;
- // cout << "INPUT nb_vertices " << nb_vertices << endl;
- // cout << "INPUT source " << source << endl;
- // cout << "INPUT sink " << sink << endl;
-
- scalar_t *el = new scalar_t[nb_edges];
- int *ea = new int[nb_edges];
- int *eb = new int[nb_edges];
+ scalar_t *edge_lengths = new scalar_t[nb_edges];
+ int *vertex_from = new int[nb_edges];
+ int *vertex_to = new int[nb_edges];
+ int *result_edge_occupation = new int[nb_edges];
for(int e = 0; e < nb_edges; e++) {
- (*file) >> ea[e] >> eb[e] >> el[e];
+ (*file) >> vertex_from[e] >> vertex_to[e] >> edge_lengths[e];
}
- // for(int e = 0; e < nb_edges; e++) {
- // cout << "INPUT_EDGE " << ea[e] << " " << eb[e] << " " << el[e] << endl;
- // }
-
- Graph graph(nb_vertices, nb_edges, ea, eb, el, source, sink);
+ find_best_paths(nb_vertices, nb_edges,
+ vertex_from, vertex_to, edge_lengths,
+ source, sink,
+ result_edge_occupation);
- graph.find_best_paths();
- // graph.print_occupied_edges();
- graph.dot_print();
+ dot_print(nb_vertices, nb_edges,
+ vertex_from, vertex_to, edge_lengths,
+ source, sink,
+ result_edge_occupation);
- delete[] el;
- delete[] ea;
- delete[] eb;
+ delete[] result_edge_occupation;
+ delete[] edge_lengths;
+ delete[] vertex_from;
+ delete[] vertex_to;
} else {