From 3fe1f714514a55322e22717eeddf76f9f019c658 Mon Sep 17 00:00:00 2001 From: Francois Fleuret Date: Tue, 21 Aug 2012 14:59:49 -0700 Subject: [PATCH] Prevent the same vertex to be added twice to the front in find_shortest_path. --- mtp.cc | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/mtp.cc b/mtp.cc index a9388f6..b400650 100644 --- a/mtp.cc +++ b/mtp.cc @@ -56,11 +56,9 @@ public: class Vertex { public: - int id; - + int id, iteration; Edge *root_edge; scalar_t distance_from_source; - Vertex *pred_vertex; Edge *pred_edge; @@ -89,7 +87,6 @@ class Graph { Edge *edge_heap; Vertex *vertices; Vertex *source, *sink; - public: Graph(int nb_vertices, int nb_edges, int *from, int *to, scalar_t *lengths, int source, int sink); @@ -174,7 +171,7 @@ void Graph::find_shortest_path(Vertex **front, Vertex **new_front) { for(int n = 0; n < nb_vertices; n++) { 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." + cerr << "DEBUG error in find_shortest_path: Edge work lengths have to be positive." << endl; abort(); } @@ -186,14 +183,18 @@ void Graph::find_shortest_path(Vertex **front, Vertex **new_front) { vertices[v].distance_from_source = FLT_MAX; vertices[v].pred_vertex = 0; vertices[v].pred_edge = 0; + vertices[v].iteration = 0; } + int iteration = 0; + int front_size = 0, new_front_size; front[front_size++] = source; source->distance_from_source = 0; do { new_front_size = 0; + iteration++; for(int f = 0; f < front_size; f++) { v = front[f]; for(Edge *e = v->root_edge; e; e = e->next) { @@ -203,7 +204,10 @@ void Graph::find_shortest_path(Vertex **front, Vertex **new_front) { tv->distance_from_source = d; tv->pred_vertex = v; tv->pred_edge = e; - new_front[new_front_size++] = tv; + if(tv->iteration < iteration) { + new_front[new_front_size++] = tv; + tv->iteration = iteration; + } } } } -- 2.39.5