+ * This is the pure C implementation of co_solve_heuristic_java().
+ */
+int co_solve_heuristic_mst(copy_opt_t *co);
+
+/**
+ * Returns the maximal costs possible, i.e. the costs if all
+ * pairs would be assigned different registers.
+ * Uses the OU data structure
+ */
+int co_get_max_copy_costs(const copy_opt_t *co);
+
+/**
+ * Returns the inevitable costs, i.e. the costs of
+ * all copy pairs which interfere.
+ * Uses the OU data structure
+ */
+int co_get_inevit_copy_costs(const copy_opt_t *co);
+
+/**
+ * Returns the current costs the copies are causing.
+ * The result includes inevitable costs and the costs
+ * of the copies regarding the current register allocation
+ * Uses the OU data structure
+ */
+int co_get_copy_costs(const copy_opt_t *co);
+
+/**
+ * Returns a lower bound for the costs of copies in this ou.
+ * The result includes inevitable costs and the costs of a
+ * minimal costs caused by the nodes of the ou.
+ * Uses the OU data structure