// LLPDijkstra: Dijkstra as an LLP schedule with a min-heap of non-fixed
// vertices keyed by d. The graph is supplied as adjacency lists
// adj[j] and weight array w[j] --- omitted here for clarity; a double
// compiler front-end would flesh these out.

class LLPDijkstra {
  int[] LLPDijkstra(int[]  dIn) {
    int[]  d = infinity;
    boolean[] fixed = false;

    setMode(PriorityQueue);
    setPriority(d[j], min);

    // A j is forbidden if not yet fixed and its current d matches the head
    // of the heap. The advance fixes it and relaxes its outgoing edges
    // (the relaxation code would be expanded here in a full front-end).
    forbidden (j) : !fixed[j] =>
      advance : fixed[j] = true;
    return d;
  }
}