public static LaneSchedulerState RecursiveSearch(LaneSchedulerState state, List<LaneSchedulerReservation> reservations, int depth, long timelimit, long time)
{
if (time > timelimit)
{
//Debug.WriteLine("TIME LIMIT EXCEEDED-1! Time was: " + time);
return null;
}
long time1 = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
//Debug.WriteLine("Reached depth: " + depth);
if (reservations.Count == 0)
{
return state;
}
reservations = (from y in reservations
select y).OrderBy(y => state.GetReservationWeight(y)).ToList<LaneSchedulerReservation>();
foreach (LaneSchedulerReservation reservation in reservations)
{
// Get applicable actions
List<LaneSchedulerAction> actions = Expand(state, reservation);
actions = (from y in actions
select y).OrderBy(y => y.weight).ToList<LaneSchedulerAction>();
// Loop for actions in a depth-first manner, backtracking if no solution is found.
for (int num = 0; num < actions.Count; num++)
{
LaneSchedulerAction action = actions[num];
state.Apply(action);
//if (!Scheduler.closedStateList.ContainsKey(state.ReservationRepr(action.reservation)))
//{
List<LaneSchedulerReservation> remainingReservations = new List<LaneSchedulerReservation>(reservations);
remainingReservations.Remove(action.reservation);
int newDepth = depth + 1;
long time2 = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
long runTime = time2 - time1;
time = time + runTime;
LaneSchedulerState solution = RecursiveSearch(state, remainingReservations, newDepth, timelimit, time);
if (solution != null)
{
//Debug.WriteLine("Placed reservation: " + action.reservation.id);
return solution;
}
else
{
//string stateRepr = state.ReservationRepr(action.reservation);
//if (!Scheduler.closedStateList.ContainsKey(stateRepr))
//{
// Scheduler.closedStateList.Add(stateRepr, 1);
//}
state.Unapply(action);
if (time > timelimit)
{
//Debug.WriteLine("TIME LIMIT EXCEEDED-2! Time was: " + time);
return null;
}
//Debug.WriteLine(state.toString());
}
//}else{
//Debug.WriteLine(" Hit an explored state!");
//Debug.WriteLine(state.toString());
//Debug.WriteLine(" " + state.ReservationRepr(action.reservation));
//state.Unapply(action);
//return null;
//}
}
//Debug.WriteLine(" Backtracking");
//Debug.WriteLine(state.toString());
}
return null;
}
public static LaneSchedulerStateReservationsPair Search(LaneSchedulerState state, List<LaneSchedulerReservation> reservations, LaneSchedulerReservation newReservation)
{
LaneScheduler.closedStateList = new Dictionary<string, int>();
Debug.WriteLine("Adding new Reservation");
if (!state.IsPossible(newReservation))
{
Debug.WriteLine(" It failed the first check");
// get other reservations
return new LaneSchedulerStateReservationsPair(null, LaneScheduler.GetAlternativeReservations(state, newReservation));
}
// if it can be applied easily
List<LaneSchedulerAction> actions = Expand(state, newReservation);
actions = (from y in actions
select y).OrderBy(y => y.weight).ToList<LaneSchedulerAction>();
if (actions.Count > 0)
{
state.Apply(actions[0]);
Debug.WriteLine(" The reservation was straight forward");
return new LaneSchedulerStateReservationsPair(state, new List<LaneSchedulerReservation>());
}
// else, search
// cut the relevant piece out of the state, so we end up with three pieces.
// Solve the middle piece, and add it to the top and bottom piece.
//List<State> statePieces = state.cutInPieces(newReservation);
List<LaneSchedulerReservation> newReservations = new List<LaneSchedulerReservation>(reservations);
newReservations.Add(newReservation);
long time1 = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
LaneSchedulerState emptyState = new LaneSchedulerState(state.numberOfLanes, state.numberOfTimeSlots, newReservations);
LaneSchedulerState newState = LaneScheduler.RecursiveSearch(emptyState, newReservations, 0, 100000, 0);
long time2 = DateTime.Now.Ticks / TimeSpan.TicksPerMillisecond;
long runTime = time2 - time1;
Debug.WriteLine(" Search took: " + runTime + " ms");
if (newState != null)
{
Debug.WriteLine(" Returning state");
return new LaneSchedulerStateReservationsPair(newState, new List<LaneSchedulerReservation>());
}
else
{
// get other reservations
Debug.WriteLine(" Returning other reservations");
return new LaneSchedulerStateReservationsPair(null, LaneScheduler.GetAlternativeReservations(state, newReservation));
}
}
