+/*construct the adjacency matrix corresponding to a graph,
+ the weights are the distances between nodes
+ */
+double *xbt_graph_get_length_matrix(xbt_graph_t g)
+{
+ int cursor = 0;
+ int in_cursor = 0;
+ int idx,i;
+ unsigned long n;
+ xbt_edge_t edge = NULL;
+ xbt_node_t node=NULL;
+ double *d = NULL;
+
+# define D(u,v) d[(u)*n+(v)]
+ n = xbt_dynar_length(g->nodes);
+
+ d = (double *) xbt_malloc(n * n * (sizeof(double)));
+
+ for (i = 0; i < n * n; i++)
+ {
+ d[i] = -1.0;
+ }
+
+ xbt_dynar_foreach(g->nodes, cursor, node)
+ {
+ in_cursor = 0;
+ D(cursor, cursor) = 0;
+
+ xbt_dynar_foreach(node->out, in_cursor, edge)
+ {
+ if (edge->dst==node)
+ idx= __xbt_find_in_dynar(g->nodes, edge->src);
+ else /*case of undirected graphs*/
+ idx = __xbt_find_in_dynar(g->nodes, edge->dst);
+ D( cursor,idx) = edge->length;
+ }
+ }
+
+# undef D
+
+ return d;
+}
+
+
+void xbt_floyd_algorithm(xbt_graph_t g, double *adj, double *d,
+ xbt_node_t * p)
+{
+ int i, j, k;
+ unsigned long n;
+ n = xbt_dynar_length(g->nodes);
+
+# define D(u,v) d[(u)*n+(v)]
+# define P(u,v) p[(u)*n+(v)]
+
+ for (i = 0; i < n * n; i++)
+ {
+ d[i] = adj[i];
+ }
+
+
+ for (i = 0; i < n; i++)
+ {
+ for (j = 0; j < n; j++)
+ {
+ if (D(i, j) != -1)
+ {
+ P(i,j) =*((xbt_node_t*) xbt_dynar_get_ptr(g->nodes, i));
+ }
+ }
+ }
+
+ for (k = 0; k < n; k++)
+ {
+ for (i = 0; i < n; i++)
+ {
+ for (j = 0; j < n; j++)
+ {
+ if ((D(i, k) != -1) && (D(k, j) != -1))
+ {
+ if ((D(i, j) == -1) || (D(i, j) > D(i, k) + D(k, j)))
+ {
+ D(i, j) = D(i, k) + D(k, j);
+ P(i, j) = P(k, j);
+ }
+ }
+ }
+ }
+ }
+
+
+
+# undef P
+# undef D
+}
+
+/*computes all-pairs shortest paths*/
+xbt_node_t *xbt_graph_shortest_paths(xbt_graph_t g)
+{
+ xbt_node_t *p;
+ xbt_node_t *r;
+ int i, j, k;
+ unsigned long n;
+
+ double *adj = NULL;
+ double *d = NULL;
+
+# define P(u,v) p[(u)*n+(v)]
+# define R(u,v) r[(u)*n+(v)]
+
+ n = xbt_dynar_length(g->nodes);
+ adj = xbt_graph_get_length_matrix(g);
+ d = xbt_malloc(n*n*sizeof(double));
+ p = xbt_malloc(n*n*sizeof(xbt_node_t));
+ r = xbt_malloc(n*n*sizeof(xbt_node_t));
+
+ xbt_floyd_algorithm(g, adj, d, p);
+
+ for (i = 0; i < n; i++)
+ {
+ for (j = 0; j < n; j++)
+ {
+ k = j;
+
+ while ((P(i, k)) && (__xbt_find_in_dynar(g->nodes, P(i, k)) != i))
+ {
+ k = __xbt_find_in_dynar(g->nodes, P(i, k));
+ }
+
+ if (P(i, j))
+ {
+ R(i, j) = *((xbt_node_t*) xbt_dynar_get_ptr(g->nodes, k));
+ }
+ }
+ }
+# undef R
+# undef P
+
+ xbt_free(d);
+ xbt_free(p);
+ return r;
+}
+
+
+static xbt_graph_t parsed_graph = NULL;
+static xbt_dict_t parsed_nodes = NULL;
+
+
+static void __parse_graph_begin(void)
+{