void new_iteration(int iteration) {
     if (iteration > 0) {
         // Swap
         dense_bitset * tmp = curiteration_bitset;
         curiteration_bitset = nextiteration_bitset;
         nextiteration_bitset = tmp;
         nextiteration_bitset->clear();
     }   
     
 }
 /**
  * Resize the internal locks for a different graph
  */
 void resize(size_t num_vertices) {
   atomic_box_vec.resize(num_vertices);
   atomic_box_vec.clear();
 }
 /** Initialize the per vertex task set */
 atomic_add_vector2(size_t num_vertices = 0) {
   resize(num_vertices);
   atomic_box_vec.clear();
 }
 void clear() {
   atomic_box_vec.clear();
 }