output-dot.txt

/* -*- mode:c -*- */

/* These functions should be added to your tree.c file */

/**
 * Output a DOT description of this tree to the given output stream.
 * DOT is a plain text graph description language (see www.graphviz.org).
 * You can create a viewable graph with the command
 *
 *    dot -Tpdf < graphfile.dot > graphfile.pdf
 *
 * You can also use png, ps, jpg, svg... instead of pdf
 *
 * @param t the tree to output the DOT description of.
 * @param out the stream to write the DOT description to.
 */
void tree_output_dot(tree t, FILE *out) {
   fprintf(out, "digraph tree {\nnode [shape = Mrecord, penwidth = 2];\n");
   tree_output_dot_aux(t, out);
   fprintf(out, "}\n");
}

/**
 * Traverses the tree writing a DOT description about connections, and
 * possibly colours, to the given output stream.
 *
 * @param t the tree to output a DOT description of.
 * @param out the stream to write the DOT output to.
 */
static void tree_output_dot_aux(tree t, FILE *out) {
   if(t->key != NULL) {
      fprintf(out, "\"%s\"[label=\"{<f0>%s:%d|{<f1>|<f2>}}\"color=%s];\n",
              t->key, t->key, t->frequency,
              (RBT == tree_type && RED == t->colour) ? "red":"black");
   }
   if(t->left != NULL) {
      tree_output_dot_aux(t->left, out);
      fprintf(out, "\"%s\":f1 -> \"%s\":f0;\n", t->key, t->left->key);
   }
   if(t->right != NULL) {
      tree_output_dot_aux(t->right, out);
      fprintf(out, "\"%s\":f2 -> \"%s\":f0;\n", t->key, t->right->key);
   }
}